Calibration of colorimetric ammonia nitrogen analyzer
LI Bo, LIU Binjie, YUAN Jing
Henan Institute of Metrology, Zhengzhou 450008, China
摘要：介绍比色法氨氮测定仪的校准方法。根据不同的应用方式和工作特性，将比色法氨氮测定仪分为I 型和Ⅱ型。对于I 型仪器选取示值误差、测量重复性、稳定性3 个计量特性进行校准；对于Ⅱ型选取测量线性、测量重复性、检出限3 个计量特性进行校准。结果表明，I 型仪器的重复性为0.5%，稳定性为0.2%～0.4%，测量范围不大于2 mg/L时，示值误差为0.13 mg/L ；测量范围大于2 mg/L 时，示值误差为3.3%～4.3% ；Ⅱ型仪器的测量线性相关系数为0.999，重复性为2.3%，检出限为0.013 9 mg/L。两种类型仪器的计量性能指标均能够满足校准方法的要求。该校准方法切实可行，可以用于比色法氨氮测定仪的校准。
Abstract：The calibration method of colorimetric ammonia nitrogen analyzer was introduced. According to different
application modes and working characteristics, colorimetric ammonia nitrogen analyzer was divided into type Ⅰ and type
Ⅱ. The three measuring characteristics of type Ⅰ ammonia nitrogen analyzer were calibrated, including indication error,
measurement repeatability and stability. The three measuring characteristics of type Ⅱ ammonia nitrogen analyzer were
calibrated, including measurement linearity, measurement repeatability and detection limit. The repeatability of type Ⅰ
instrument was 0.5%, and its stabilities were 0.2%-0.4%. When the measuring range was not more than 2 mg/L, the error of
type Ⅰ instrument was 0.13 mg/L, and when the measuring range was larger than 2 mg/L, the error of type Ⅰ instrument
was 3.3%-4.3%. The linear correlation coefficient of type II instrument was 0.999, the repeatability was 2.3%, and the
detection limit was 0.013 9 mg/L. The measurement performance indexes of both types of instruments could meet the
requirements of calibration methods. The calibration method is feasible and can be used for calibration of colorimetric
ammonia nitrogen analyzer.
Keywords：colorimetry; ammonia nitrogen analyzer; calibration
李博，刘斌杰，袁晶. 比色法氨氮测定仪的校准[J]. 化学分析计量，2019，28(Z1)：59-62.
LI B，LIU B J，YUAN J. Calibration of colorimetric ammonia nitrogen analyzer[J]. Chemical analysis and meterage，2019，28(Z1)：59-62.