DETERMINE THE EXPERIMENTAL PARAMETERS OF UREA RELEASE FROM SMART UREA FERTILIZER

Abstract

Smart urea fertilizers (SUF), in which a coating layer (encapsulation) prevents the direct interaction of the nutrients with the environment in order to regulate the release of nutrients and maintain nutrient content at an appropriate level with the crop. The nutrients release is important for evaluating the quality and properties of the products. The aim of the study is to determine the mechanism and nutrient release model of SUF, from which to survey and calculate important experimental parameters of release process. SUFs are produced by pan coating systems with the coating, which is made from environmentally friendly, biodegradable polymer materials. Particle size and the coating thickness were determined by image analysis method using MATLAB software, urea release was measured by a spectrophotometric method. The results of the study showed that the mechanism and release model of SUF is the membrane diffusion model. Process parameters such as: water permeability and diffusion coefficient of membrane, delay time, stability time and urea release rate are also determined. These are important parameters to establish a nutrient release model that is compatible with crop needs.