US 12,215,071 B2
Thermal stripping urea plant and process
Wilhelmus Hubertus Geurts, Sittard (NL)
Assigned to Stamicarbon B.V., Sittard (NL)
Filed by Stamicarbon B.V., Sittard (NL)
Filed on Mar. 19, 2024, as Appl. No. 18/609,842.
Application 18/609,842 is a division of application No. 18/447,469, filed on Aug. 10, 2023, granted, now 11,958,792.
Application 18/447,469 is a division of application No. 17/636,257, granted, now 11,814,340, issued on Nov. 14, 2023, previously published as PCT/NL2021/050395, filed on Jun. 23, 2021.
Claims priority of application No. 20181754 (EP), filed on Jun. 23, 2020.
Prior Publication US 2024/0279165 A1, Aug. 22, 2024
Int. Cl. C07C 273/04 (2006.01); B01D 5/00 (2006.01); B01J 3/02 (2006.01); B01J 3/04 (2006.01)
CPC C07C 273/04 (2013.01) [B01D 5/0075 (2013.01); B01J 3/02 (2013.01); B01J 3/042 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A urea plant comprising a high pressure synthesis section comprising a reaction zone, a thermal stripper, and a carbamate condenser, the plant further comprising a first medium pressure recovery section having an inlet connected to an outlet for stripped urea solution of said thermal stripper,
wherein the high pressure synthesis section comprises a high pressure separator configured for separating a high pressure reaction mixture from the reaction zone into a first stream and a second stream, the first stream and the second stream both containing a liquid phase containing urea; and
wherein the high pressure separator has a first outlet for the first stream connected to an inlet of said thermal stripper, and a second outlet for the second stream connected to a second medium pressure recovery section;
wherein the first medium pressure (MP) recovery section comprises a first MP decomposer, a first MP carbamate condenser, a medium pressure separation column, and an ammonia condenser;
wherein said first MP decomposer is configured for subjecting the stripped urea solution to decomposition to give a MP urea solution and a gas stream from the MP decomposer,
wherein said first MP carbamate condenser is configured for subjecting the gas stream from the MP decomposer to condensation,
wherein said medium pressure separation column is configured for separating a stream from said first MP carbamate condenser into a MP carbamate solution and an ammonia-containing gas stream,
wherein said ammonia condenser is configured for subjecting the ammonia-containing gas stream to condensation to give an ammonia condensate stream;
wherein the second MP recovery section comprises:
an MP adiabatic flashing unit configured for expanding the second stream from high pressure to medium pressure in the second MP recovery section thereby obtaining a gaseous stream and a flashed MP urea solution;
a second MP decomposer configured for subjecting the flashed MP urea solution to decomposition to give treated urea solution and a gas stream from the second MP decomposer;
a second MP carbamate condenser, configured for subjecting the gas stream from the second MP decomposer to condensation to give carbamate solution; and
a gas flow line for said gaseous stream from said MP adiabatic flashing unit to said first medium pressure (MP) recovery section.