| 摘要 |
This invention provides a pneumatic steam dryer (1.1; 1.2; 1.3; 1.4) for producing bio fuel pellets, said pneumatic steam dryer being adapted to operate above atmospheric pressure, comprising -a circulation conduit system which in operation of the pneumatic steam dryer (1) is pressurized and filled with steam, -a heat exchanger (6,6') connected into said circulation conduit system for heating said steam, -an inlet feeding device (8) connected to said circulation conduit system for feeding bulk material into said circulation conduit system, -a drying conduit (11) connected into said circulation conduit system wherein said bulk material is dried by heat transfer from said steam thereby forming surplus steam, - separating means (12; 12') connected to said drying conduit (11) for separating said bulk material from said steam, said separating means (12;12') comprising a steam outlet (14) and a bulk material outlet (15; 15'), -a fan (5) connected into said circulation conduit system for pneumatically conveying said bulk material suspended in said steam from said inlet feeding device (8) to said separating means (12; 12'), said pneumatic steam dryer further comprises a pelleting device (16.1;16.2) integrated in the circulation conduit system, wherein said pelleting device (16.1;16.2) is connected to said bulk material outlet (15; 15') of the separating means (12; 12'), and the total mass flow of bulk material is conveyed from the separating means (12; 12') to the pelleting device (16.1; 16.2). The invention also provides a process for producing fuel pellets in such a pneumatic steam dryer. |
