LAUSR

This work is dedicated to researching the possibilities of using starch coating for slow-release fertilizers. Urea was used as nitrogen containing component, because it is the most suitable for the production of slow-release nitrogen fertilizers and has the highest concentration of nitrogen – 46.6 %. During the studies, native potato starch film was prepared and its stability was evaluated, subsequently, urea was coated with starch film/coating and the influence on properties of fertilizer granules (hygroscopicity and strength) was evaluated. Single and/or multiple layered films were formed during the coating process and the influence of coating thickness on urea solubility was researched. It was found that the mechanical properties of urea with double coating change quite insignificantly while coating reduces the solubility of urea by more than 20 %.