Cooling Process Intensification for Granular Mineral Fertilizers in a Multistage Fluidized Bed Device

The design of a multistage cooler with several inclined perforated shelves for cooling granular fertilizers is presented and explained in the article. It is proved that such device has certain technical and energy advantages compared with typical designs of coolers. For this purpose, physical modeling of the hydrodynamic structure of the fluidized bed in the shelf apparatus was carried out. The formation of hydrodynamic regimes that differ in their hydrodynamic structure depending on the design parameters of the shelf contact elements is justified. A mathematical model of the kinetics of cooling granules in a fluidized bed is developed, which makes it possible to determine the cooling time of granules and calculate the temperature profile in a suspended layer. The optimal design parameters of the shelf cooler were experimentally determined, at which the granules are intensively cooled to the technologically required temperature. The results of experimental studies are presented, which confirm the efficiency of granular fertilizers cooling in multistage shelf apparatus with less energy consumption.