Horizontal and vertical columns contain numbers corresponding to different fertilizers. Possibility of mixing is shown in box. White boxes indicate that the mixing is possible, black ones show that it’s not allowed. Hatched boxes correspond to the mixtures where unfavorable processes are relatively slow. Letter «G» denotes mixtures mixtures where gas emission can be observed and «R» denotes mixtures where retrogradation of Р2О5 can be observed.The present diagram is partly filled with information obtained from the research work. Compacted fertilizers can be produced in the form of granulated mixtures. The material is granulated after or during mixing of components. In the past ready powder blends were granulated with water and then coated and dried. At present it’s common to combine mixing of fertilizers together with a chemical treatment – ammoniation by ammonia gas and liquid ammoniates, introduction of acids (phosphorous, nitric, sulfuric) into the mixture and neutralizing materials, solutions and melts instead of water in granulation process.In general granulation of mineral fertilizers is carried at 75-1000С. In such conditions a part of water is evaporated (up to 20%). It results in crystallization of salts on the surface of solid particles and produced granules from oversaturated solution and also from melt. Moreover granules of larger size are produced in their contact points.Agglomeration processes carried in different granulators depend on mixture composition, its moisture, physical and chemical properties of initial materials, layer high in granulators, RPM, elevation angle of granulator, temperature, recycle ratio etc.PFD of compacted fertilizers in presented in Figure 3.2.In individual cases when heat of chemical reaction carried in the system is enough to remove remaining moisture drying stage can be removed from PFD.
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