有机肥料总氮含量的测定方法研究

氮作为有机肥料养分的重要来源，其含量是评价有机肥料质量的一项重要指标。为了给有机肥料总氮含量的测定提供快速且精确的测定方法。选择了6个有机肥料样品，用H2SO4-H2O₂消煮，分别用连续流动注射分析仪和半自动凯氏定氮仪测定消煮液中的全氮含量，以探讨不同方法快速而精确地测定有机肥料总氮含量的可行性。结果表明，利用连续流动注射分析仪和半自动凯氏定氮仪测定方法的结果间没有显著性差异，相对标准偏差均在5%以下，且连续流动注射分析仪加标回收率为97.5%～102.0%。同时由于连续流动注射分析仪测定有机肥料总氮具有快速准确、试剂用量少的优点，适合大批量有机肥料总氮的测定分析。

Study on Different Methods for Determining the Total Nitrogen Content in Organic Fertilizers

As an important source of organic fertilizer nutrients, nitrogen content is an important index for evaluating the quality of organic fertilizers. In this paper, the purpose is to explore the feasibility of determining the total nitrogen content of organic fertilizers by continuous flow injection analyzer, 6 organic fertilizer samples were selected and digested with H2SO4-H2O₂, the contents of total nitrogen in the digests were determined by continuous flow analyzer and semi-automatic kjeldahl nitrogen determination apparatus, respectively. The result showed that no significant difference between the continuous flow analyzer and the semi-automatic kjeldahl nitrogen determination apparatus was detected, relative standard deviation numbers were less than 5%, and the standard recovery rate of the continuous flow analyzer was 97.5% to 102.0%. The flow injection analyzer has the advantages of rapid determination of total nitrogen in organic fertilizer and less reagent consumption, which is suitable for the analysis of total nitrogen in large quantities of organic fertilizer.