Installation and process for crystallizing and drying granular polymer material

An installation (1) for crystallizing and drying granular polymer material with a low level of crystallinity comprising:

• at least one crystallization hopper (10) which is connected to a crystallization line (11), via which there is introduced into the at least one crystallization hopper (10) a first gas flow which is heated to a first temperature which is suitable for increasing the level of crystallinity of the granular polymer material;
• an agitation member (16) which is associated with the at least one crystallization hopper (10) and which is provided to maintain the granular material in an agitated state inside the at least one crystallization hopper (10);
• at least one heating hopper (20) which is arranged downstream of the at least one crystallization hopper (10) and which is provided with a heating unit (21) which is provided to heat the crystallized granular polymer material to a second temperature which is greater than the first temperature,
• at least one drying hopper (30) which is arranged downstream of the at least one heating hopper (20) and which is connected to a depressurization circuit (31) which is provided to obtain in the drying hopper a predefined level of pressure reduction and to dry the granular polymer material,
• at least one supply hopper (40) which is arranged downstream of the drying hopper and upstream of a transformation machine (100) for the granular polymer material.