2011 Mennen Stamicarbon 7893298 Concentrating aqueous ammonia carbamate stream

The invention relates to a method for concentrating an aqueous ammonium carbamate stream, which has been formed in a process for the preparation of urea, has a pressure between 0.20 MPa and 0.9 MPa, a temperature between 35 °C and 95 °c., and contains at least 25 wt. % H20, comprising: a pressure increase step, in which the aqueous ammonium carbamate stream is increased in pressure to a pressure between 1.0 MPa and 7 MPa; a condensation step, in which the aqueous ammonium carbamate stream is contacted with a gas stream, which has been formed in a process for the preparation of melamine and which consists essentially of NH3, CO2 and optionally H20 and has a lower H20 content than the aqueous ammonium carbamate stream, the gas stream being absorbed in the aqueous ammonium carbamate stream in such a way that a concentrated annnonium carbamate stream is fonned that contains between 15 and 35 wt. % H20; a discharge step, in which the concentrated ammonium carbamate stream is separated and discharged.
 
 
 
 

Share this on:
Twitter
LinkedIn
UreaKnowHow

UreaKnowHow.com is an independent group of nitrogen fertilizer specialists with an impressive number of years experience in designing, maintaining and operating nitrogen fertilizer plants.

Solution Providers offer their solutions to improve our member’s plants performance.