| 摘要 |
After moistening dry granules in a hopper for moistening the granules are moved in the direction of working space of the device. During movement the moistened granules prior to admission to the device workspace are treated by a flow of coolant, and the process of primary drying and removal of moisture from the surface layer is carried out with subsequent heating on the granule with gradual formation of a porous film. After initial drying process, removing moisture from the surface layer and heating surface layer the granules enter the working space of device to contact with vortex of high-temperature fluid flow. In the created vortex suspended layer a full heating the granule is carried out on entire section with removal of moisture from its core and completion of the process of forming a porous surface layer on the granule. Commercial fraction in the form of dry granules with the porous surface layer with a certain size and weight is removed from the device. The fraction containing moisture and characterized by weight greater as compared with the commercial fraction, continues to be dried up to the moment of occurrence of conformity of its weight with the weight of commercial fraction. The method is implemented in a device comprising a vertical conical body with a lid and an additional open cone placed in the middle of the vertical conical body concentrically with it and rigidly connected thereto, the cone forms with the vertical conical body an annular gap, which is limited by the smaller bases of the cone and an additional open vertical cone. The device also comprises a nozzle tangentially located with respect to the axis of device for supplying a high-temperature coolant, a vortex gas distribution unit located on the same axis with the additional open cone and intended for transportation of granules in the additional open cone. The device is equipped with a pneumatic unit for transportation of wet granules from the hopper of moistening, a pipe to supply dry granules and wet air, a pipe for removal of finished granules of porous structure, and a unit for supply and distribution of the coolant for the first stage of contact with the moistened granule. The technical result consists in provision of creation of the granules with porous structure and monodispersity of granules up to 93 %, that improves the quality and properties of the product at the level of strength of finished product of 400-450 g/granule, retention capacity of a granule for 9-9.5 %, 100 % friability of granules. |
