US 11,707,866 B2
Process for drying granular polymeric material and plant operating according to said process
Rinaldo Piva, Borgoricco (IT)
Assigned to PEGASO INDUSTRIES S.P.A., Borgoricco (IT)
Appl. No. 16/605,813
Filed by Pegaso Industries S.p.A., Borgoricco (IT)
PCT Filed Apr. 19, 2018, PCT No. PCT/IB2018/052704
§ 371(c)(1), (2) Date Oct. 17, 2019,
PCT Pub. No. WO2018/193396, PCT Pub. Date Oct. 25, 2018.
Claims priority of application No. 102017000043004 (IT), filed on Apr. 19, 2017.
Prior Publication US 2021/0276224 A1, Sep. 9, 2021
Int. Cl. A45D 20/12 (2006.01); B29B 13/06 (2006.01); B29B 9/16 (2006.01); B29B 13/08 (2006.01); F26B 3/08 (2006.01); F26B 5/04 (2006.01); F26B 17/14 (2006.01)
CPC B29B 13/065 (2013.01) [B29B 9/16 (2013.01); B29B 13/08 (2013.01); F26B 3/08 (2013.01); F26B 5/041 (2013.01); F26B 17/14 (2013.01); F26B 2200/08 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A process for drying granular polymeric material, comprising:
dehumidifying said granular polymeric material by a first flow of gas introduced into said granular polymeric material at a first temperature of between 100° C. and 150° C.;
heating said dehumidified granular polymeric material to a second temperature that is greater than said first temperature;
drying said granular polymeric material heated to said second temperature by applying a predefined vacuum level; and
transferring said dried granular polymeric material to a feed hopper (40) that is provided upstream of a machine (100) for working said granular polymeric material, wherein said first flow of gas is air that is taken from the environment and is not recirculated and wherein said granular polymeric material is heated to said second temperature by a second flow of gas introduced, without prior dehumidification, into said granular polymeric material by a circuit (22) for recirculating said second flow of gas.