杜马斯燃烧法测定有机肥料中全氮含量的可行性研究

Feasibility Study on Determination of Total Nitrogen Content in Organic Fertilizer by Dumas Combustion Method

考察了杜马斯燃烧法和行业标准《有机肥料》(NY/T 525—2021)中的方法测定有机肥料中全氮含量的精密度和加标回收率。结果表明:NY/T 525—2021中的方法测得5个有机肥料样品的全氮质量分数为1.76%~3.83%,加标回收率为99.5%~101.0%;杜马斯燃烧法测得5个有机肥料样品的全氮质量分数为1.70%~3.84%,加标回收率为98.1%~104.7%;两种方法的相对标准偏差为0.18%~2.45%,均可满足有机肥料中全氮含量的测定要求。与NY/T 525—2021中的方法相比,杜马斯燃烧法具有操作便捷安全、自动化程度高、测定耗时短等特点。

The precision and recovery of the determination of total nitrogen content in organic fertilizers by Dumas combustion method and the method in industry standard"Organic Fertilizer"(NY/T 525—2021)are investigated.The results show that the total nitrogen mass fraction of the five organic fertilizer samples measured by the method in NY/T 525—2021 is 1.76% to 3.83%,and the recovery is 99.5% to 101.0%.The mass fraction of total nitrogen in five organic fertilizer samples measured by Dumas combustion method is 1.70% to 3.84%,and the recovery is 98.1% to 104.7%.The relative standard deviation of the two methods is 0.18% to 2.45%,both of which can meet the requirements of the determination of total nitrogen content in organic fertilizer.Compared with the method in NY/T 525—2021,Dumas combustion method has the characteristics of convenient and safe operation,high degree of automation and short measurement time.