Optimization of Liquid Complex Fertilizer Formulations Using Phase Diagrams of Multicomponent Systems

Abstract

The paper describes a method for the optimization of liquid complex fertilizer (LCF) formulations using phase diagrams of multicomponent water–salt systems. The chosen optimization criteria are the concentration of solution and the set of salts that provide the most concentrated fertilizer at the set ratio N : P2O5 : K2O. The opportunities of the method are shown for exemplary three- and four-component systems. The compositions of eutonic solutions and the ratios of nutrients calculated for them are given. Experimental data confirm the influence of the salt set and a solubilizer (urea) on the solution concentration. The number of optimal compositions becomes greater as the number of components in the system increases. Phase diagrams help to determine whether the liquid fertilizer composition belongs to the 15 homogeneous regions and thereby to guarantee its long-term storage stability.