The processes of dehydration and granulation are associated with the heat transfer to the solid particles from the gas coolant, which acts as a fluidizing agent and causes the stochastic movement of the granular material in the apparatus. To implement the layered structure mechanism of granulation of organic-mineral fertilizers it is necessary to ensure intensive circulation of granular material with intensive gradual passage through the appropriate technological zones of the apparatus. The main problem is the low efficiency of interphase exchange in the gas-liquid-solid system and the formation of agglomerates during granulation with the injection of a liquid heterogeneous solution into the bed of solid granular material. In this work the conditions for increasing the efficiency of the transfer processes when using an inhomogeneous jet-pulsating mode of fluidization were determined. Analysis of the intensity of renewal of the contact surface of the phases when using inhomogeneous jet-pulsating fluidization in the self-oscillating mode was carried out. It was established that the use of this mode of fluidization allows getting a significant intensification of heat and mass transfer processes due to the activation of diffusion-controlled processes and an increase in the dynamics of interphase contact exchange by 1.9÷2.9 m2/s, which is 27÷41% of the total surface of the material in device.

An increase in the intensity of diffusion-controlled processes during granulation is provided by apparatuses with non-homogeneous fluidization, the hydrodynamics of which significantly depends on the structural features of the granulator chamber and the gas distributing device (GDD). The main problem is the formation of stagnant zones on the working surface of GDD, which, when supplying a coolant with temperature that exceeds the melting point of granules, leads to the melting of solids and the termination of the process. In this work, the simulation of hydrodynamics in the granulator chamber was carried out using SolidWorks 2022 SP2 for 4 types of gas distribution devices (GDD) of different configurations with different values ​​of the cross-section coefficient of GDD. The analysis of the simulation results shows that the most significant influence on the hydrodynamic activity index near the surface of GDD iha has the cross-section coefficient of GDD φ, since even an insignificant increase in the value of φ from 3.0 to 3.5% leads to a significant decrease in the hydrodynamic activity index iha by at least 1.4 times for all considered types of GDD. The simulation of hydrodynamics was carried out without taking into account the presence of solid granular material in the granulator chamber and near the surface of GDD plate.