Urea synthesis process
Abstract
Abstract A UREA SYNTHESIS PROCESS IN WHICH THE PRESSURE OF THE EFFLUENT MELT FROM THE UREA SYNTHESIS AUTOCLAVE IS REDUCED TO AN INTERMIDIATE LEVEL OF 65 TO 135 KG./SQ. CM., AND THE OFF-GAS EVOLVED AT THIS RELATIVELY HIGH PRESSURE IS SEPARATED FROM THE LIQUID EFFLUENT, WHICH IS THEN DISTILLED TO PRODUCE FURTHER HIGH PRESSURE OF-GAS. THE OFF-GAS STREAMS OF LOW WATER VAPOR CONTENT ARE COMBINED AND CONDENSED, PREFERABLY BY BEAT EXCHANGE WITH WATER WHICH IS VAPORIZED TO PRODUCE STEAM, AND THE PROCESS CONDENSATE IS RECYCLED TO UREA SYNTHESIS AS RECYCLE AMMONIUM CARBAMATE SOLUTION WHICH IS REACTED WITH FEED STREAMS AMMONIA AND CARBON DIOXIDE AT HIGH PRESSUER TO SYNTHESIZE UREA AND FORM THE EFFLUENT MELT. THE RESIDUAL LIQUID PHASE AFTER HIGH PRESSURE DISTILLATION IS PASSED AT REDUCED PRESSURE TO FURTHER OFF-GAS SEPARATION AND DISTILLATION, AND LOW PRESSURE OFF-GAS STREAMS ARE COMBINED AND CONDENSED TO A LIQUID CONDENSATE WHICH IS PRESSURIZED AND ADDED TO THE COMBINED HIGH PRESSURE OFF-GAS STREAM OR TO THE HIGH PRESSURE RECYCLE AMMONIUM CARBAMATE SOLUTION.
Inventors
- 👤 S Harada
- 👤 M Karafian
Bibliographic Details
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