公开(公告)号：DE3031124A1

公开(公告)日：1982-04-08

申请号：DE3031124

申请日：1980-08-18

Applicant: BASF AG

Inventor： BORHO KLAUS DIPL ING DR ,  FROMM DIETER DIPL CHEM DR ,  SCHIER ERNST-JUERGEN DIPL CHEM ,  SCHNEEHAGE HANS HENNING DIPL C ,  WIDMANN ALFRED DIPL ING DR

IPC: C07C273/10 ,  C07C67/00 ,  C07C239/00 ,  C07C273/12 ,  C07C273/16 ,  C07D251/62 ,  C07D251/60

Abstract: A process for isolating liquid urea and its thermal decomposition products from the off-gas of melamine synthesis, which gas has been freed from melamine by fractional condensation and then been washed with molten urea, wherein the off-gas, containing 2-10 kg of melt per kg of pure gas, is passed at 8-30 m/sec tangentially into the upper part of an axially symmetrical separation zone. As a result of the rotation imparted to the gas/liquid mixture, the two phases are separated from one another, and both pass downward through the separation zone. The gas and liquid are separately taken off at the bottom end of the separation zone. The residence time of the gas mixture in the separation zone is not less than 0.5 second.

公开(公告)号：DE2525781A1

公开(公告)日：1976-12-16

申请号：DE2525781

申请日：1975-06-10

Applicant: BASF AG

Inventor： HILLENBRAND ENGELBERT DIPL CHE ,  FROMM HERMANN DIETER DIPL CHEM ,  WIDMANN ALFRED DIPL ING DR

IPC: C07D251/56 ,  B01D5/00 ,  B01D53/44 ,  B01D53/74 ,  C07D251/60 ,  C07D251/62