Urea (NH4CO), a common industrial fertilizer, is produced from ammonia (NH3) and carbon dioxide (CO). The...

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Urea (N₂H4CO), a common industrial fertilizer, is produced from ammonia (NH3) and carbon dioxide (CO₂). The reaction is given by 2NH3 + CO₂ N₂H4CO + H₂O The ammonia contains nitrogen (N₂) which acts as an inert during this reaction. A flowchart of the process is provided below. The NH3 entering the reactor has a Single Pass Conversion of 53.2% and an Overall Conversion of 91.9%. After leaving the reactor, the stream enters a distillation column where 97% of the urea in the column feed leaves through the column's bottom stream. Only this component and a small portion of the water leaves the bottom of this column. The water composition in the urea product is 0.1 mole%. The remaining material fed to the first column exits through the top. This remaining material is fed to a second column where all water and urea in the column feed leaves through the column's bottom stream. The ammonia- rich stream leaving the second column's top stream is recycled back to a mixer where fresh ammonia and carbon dioxide are added. The effluent of this mixer is then fed to the reactor. A purge is installed on the recycle stream to remove the nitrogen from the system. This purge is operated so that 10% of the second column's top stream is purged. When operated at a fresh feed rate of 1,200 lbmole/hr of a 60 mole% NH3/38 mole% CO₂/2 mole % N₂ mixture, the urea component flowrate leaving the first column's bottom stream is 321 lbmole N₂H4CO/hr. Determine the component molar flowrates (lbmole/hr) of all streams in the diagram on the following page as well as the overall and single-pass conversions of ammonia. Fresh NH3 N₂ CO₂ Mixer Reactor First Column N,H CO-Rich Stream Second Column Purge N₂ NH, CO₂ H₂O-Rich Stream Urea (N₂H4CO), a common industrial fertilizer, is produced from ammonia (NH3) and carbon dioxide (CO₂). The reaction is given by 2NH3 + CO₂ N₂H4CO + H₂O The ammonia contains nitrogen (N₂) which acts as an inert during this reaction. A flowchart of the process is provided below. The NH3 entering the reactor has a Single Pass Conversion of 53.2% and an Overall Conversion of 91.9%. After leaving the reactor, the stream enters a distillation column where 97% of the urea in the column feed leaves through the column's bottom stream. Only this component and a small portion of the water leaves the bottom of this column. The water composition in the urea product is 0.1 mole%. The remaining material fed to the first column exits through the top. This remaining material is fed to a second column where all water and urea in the column feed leaves through the column's bottom stream. The ammonia- rich stream leaving the second column's top stream is recycled back to a mixer where fresh ammonia and carbon dioxide are added. The effluent of this mixer is then fed to the reactor. A purge is installed on the recycle stream to remove the nitrogen from the system. This purge is operated so that 10% of the second column's top stream is purged. When operated at a fresh feed rate of 1,200 lbmole/hr of a 60 mole% NH3/38 mole% CO₂/2 mole % N₂ mixture, the urea component flowrate leaving the first column's bottom stream is 321 lbmole N₂H4CO/hr. Determine the component molar flowrates (lbmole/hr) of all streams in the diagram on the following page as well as the overall and single-pass conversions of ammonia. Fresh NH3 N₂ CO₂ Mixer Reactor First Column N,H CO-Rich Stream Second Column Purge N₂ NH, CO₂ H₂O-Rich Stream