过硫酸盐缓释材料释放过程模型构建

Model establishment for simulating release process of slow-released persulfate material

为预测评估过硫酸盐缓释材料的释放性能,对释放过程模型的构建以及模型的验证进行了研究。借助微积分思想,从材料体的概化分割、初始条件设定、每个小单元的状态标定、各个小单元中过硫酸钾的迁移变化量以及材料最外层释放过硫酸盐的量5个方面构建过硫酸盐缓释材料释放模型,利用Excel-VBA编程实现其释放过程模拟。采用欧盟标准NEN7375测试过硫酸盐缓释材料释放性能并获得模型参数。通过输入相关模型参数得到过硫酸盐动态迁移过程及其释放特征曲线,并利用实测数据与模拟数据进行拟合校验。结果表明,模型模拟值与实测值拟合较好,平均误差为1.88%,表明该模型设计合理,能够准确模拟过硫酸盐缓释材料释放过程,可作为缓释材料优化设计工具。

The construction and validation of the release process model were studied for predicting and estimating the performance of the slow-released persulfate material. Based on the idea of calculus,five aspects( including generalized segmentation of the material,setting the initial conditions,marking the state of each small unit,the variable quantity of persulfate migration and the release amount of the persulfate through the outermost material) were considered to establish the model for simulating the release process of slow-released persulfate material,and Excel VBA was used as the programming tool. During the preparation of slow-released persulfate material,NEN7375( EU's standard) was applied in testing the release performance and confirming the parameters of the model. On the base,the curve of the migration and dynamic release process was acquired,and the measured data were compared with the simulated data to validate the model. The results showed that the average error was1. 88% between the measured data and the simulated data. It indicated that the model could exactly simulate the release process of slow-released persulfate material. The model could serve as a tool for optimizing design of slowreleased persulfate material.