Kinetics of heat exchange with the capsulation of mineral granules suspension of chicken manure in a fluidized bed apparatus

The purpose of this work is to study the basic laws of heat exchange process of capsulated organic substance of mineral fertilizer of prolonged action. This paper is devoted to theoretical and experimental researches of process of mineral fertilizer granules covering with organic suspension in the form of liquid poultry manure. Working temperature range was detected, when solid competent layer of dry poultry manure was formed on particle surface, that promoted complete organic encapsulation of mineral granules. Particles aggregation kinetics in fluidized bed was investigated. Thereby it was found that granules enlargement by organic substance with working conditions was characterized by proportional and surface (normal) growth ? without formation of new granulation organic centers. It allowed to enlarge all granules to market size. The prospects of using capsule shell as a material of chicken manure suspension is shown, which prevents it from entering the raw form into the environment, and due to the organic origin of material is not contaminated soil. Detailed methodology of heat exchange research in the capsulation mineral granules of organic suspension is presented. Based on these experimental values carried out calculation of convective heat transfer coefficient of thermal agent (air) to the surface of the solid particles in the evaporation of the suspension. Experimentally and theoretically studied the kinetics of heat exchange during the coating of mineral granules suspension of chicken manure and the terms of convective heat transfer in fluidized bed. The resulting research, the criterial dependence makes it possible to predict heat transfer coefficient for the process of coating urea granules of chicken manure suspension. Mathematic model of process of mineral fertilizer granules covering with organic suspension was developed. Theoretic calculations were confirmed by results of experimental researches (inaccuracy did not exceed 8,4 %); it means that this mathematic model can be used for calculation of investigated process. Engineering analysis methods of encapsulation process were developed on the basis of received theoretical dependencies.