包膜氯化钾养分释放期快速预测研究

Study of Fast Prediction of Nutrient Release Duration of Coated Potassium Chloride

采用水中浸提法,按照行业标准《控释肥料》(HG/T 4215—2011)对5种相同膜材料的包膜氯化钾的钾素释放特征进行了评价。结果表明:膜重质量分数为6.33%~9.22%的包膜氯化钾符合初期养分释放率≤12%、28 d养分累积释放率≤75%的行业标准要求;随着膜重质量分数的增大,样品的养分释放期随之延长。用100℃快速浸提火焰光度计法建立了预测包膜氯化钾在25℃水中的养分释放期的回归方程(R^2>0.95),结果在25℃养分释放期为85~104 d的包膜氯化钾的预测值与实测值相差0~1 d,相对误差<0.96%。

By water extraction method, in accordance with industry standard ＂Controlled-Release Fertilizer＂ （ HG/T 4215-2011 ）, an evaluation is carried out of potassium release characteristics of 5 kinds of coated potassium chlorides with the same coating material. The results show that coated potassium chloride, which coating mass fraction is between 6.33% - 9.22%, meets the industrial standard requirements that nutrient release rate is less than or equal to 12% in initial stage, and 28 d nutrient accumulative release rate is less than or equal to 75%; with the increase of coating mass fraction, the nutrient release duration of the sample is prolonged accordingly. Using 100 ℃ fast extraction flame photometer method, a regression equation（R2 〉 0.95）, which is used to predict nutrient release duration of coated potassium chloride in 25 ℃ water, is established. At temperature of 25 ℃, the differences between calculated predictive values and measured values of coated potassium chloride, its nutrient release duration is 85 -104 d, are 0 -1 d, the relative error is less than 0.96%.