桐油包膜复合肥料单个颗粒包膜透过性及养分释放特性的拟合研究  

A study on permeability of the coating and nutrient release features for the single granules of tung oil-coated compound fertilizers by curve-fitting methods

作　　者：唐辉[1] 张晓春[2] 施卫省[2] 王亚明[1] 戈振扬[2] 

机构地区：[1]昆明理工大学生物与化学工程学院,云南昆明650224 [2]昆明理工大学现代农业工程学院,云南昆明650224

出　　处：《计算机与应用化学》2005年第8期587-591,共5页Computers and Applied Chemistry

基　　金：国家自然科学基金资助项目(20264002)云南省自然科学基金资助项目(2001B0009M)

摘　　要：将Shaviv方程和Richards函数用于桐油包膜复合肥料单个颗粒养分释放数据的拟合,估算出养分释放的滞后时间(tlag)、包膜的肥料透过系数P(?)及养分释放的速度常数k和养分释放曲线的形状因子do结合包膜复合肥料颗粒的粒径r和包膜厚度l探讨了两组拟合参数与养分释放实测结果之间的关系。结果表明,两种方法均能很好地对养分释放曲线进行拟合并对养分释放规律进行正确的描述,桐油包膜的P(?)均值为2.1 ×10-4cm2day-1,桐油包膜复合肥料单个颗粒以滞后时间接近于0day,平均养分释放速度常数0.24day-1释放其养分。养分释放曲线的形状因子介于-1.00--0.45之间,养分释放曲线兼有饱和型和S型曲线的特征,t50与k及t50和k与rl/P(?)之间均有良好的线性相关性。Both Shaviv equation and Richards function had been applied to experimental data of nutrient release for the single granules of tung oil-coated compound fertilizers, and the lag time tlag of nutrient release, fertilizer permeability Ps of coating and rate constant k, curve shape parameter d of nutrient release were estimated simultaneously. Combined with radius r and coating thickness l of the single granules, the relationships between the fitting parameters obtained by two methods and the experimental results were discussed. The resuits shown that both methods could be applied to fit the curve of the nutrient release and properly described it , fertilizer permeability Ps estimated for the coating materials was 2. 1 × 10^-4 cm^2day^-1. The single granules released theirs nutrient with a lag time very closed to 0day and average release rate constant 0.34day^-1, their nutrient release pattern had both features of saturation curve and sigmoidal curve as curve shape parameters d were between - 1.00 - - 0.45, but there were good linear relationships between t50 （ the time at which accumulative nutrient release reached 50 % ） and k, t50 ＆ k and rl/P respectively.

关 键 词：桐油包膜复合肥料 单个颗粒 养分释放曲线 拟合 包膜透过系数 

分 类 号：TQ44[化学工程—化学肥料工业]