| 摘要 |
For the separation of substantially pure carbon dioxide and a gas enriched in hydrogen, said gases being especially suitable for the production of urea via an intermediate ammonia synthetic and reaction with CO4 a system is provided of A. SCRUBBING A RAW GAS CONSISTING ESSENTIALLY OF CARBON DIOXIDE, HYDROGEN AND HYDROGEN SULFIDE IN A FIRST SCRUBBING STAGE WITH A FIRST FRACTION OF PARTIALLY LOADED PHYSICAL SCRUBBING AGENT, E.G., METHANOL, TO OBTAIN A PARTIALLY SCRUBBED RAW GAS DEPLETED IN H2S and a more loaded scrubbing agent; B. SCRUBBING SAID PARTIALLY SCRUBBED RAW GAS IN A SECOND STAGE WITH PHYSICAL SCRUBBING AGENT TO OBTAIN A FURTHER SCRUBBED RAW GAS ENRICHED IN HYDROGEN AND SAID PARTIALLY LOADED PHYSICAL SCRUBBING AGENT; C. SUBJECTING SAID MORE LOADED SCRUBBING AGENT TO AT LEAST ONE (PREFERABLY TWO) PRESSURE REDUCING STAGES TO OBTAIN A GASEOUS PHASE THEREFROM; D. SUBJECTING A SECOND FRACTION OF SAID PARTIALLY LOADED SCRUBBING AGENT TO AT LEAST ONE PRESSURE-REDUCING STAGE TO OBTAIN REDUCED PRESSURE LIQUID PHASE SUBSTANTIALLY FREE OF HYDROGEN SULFIDE; AND E. SCRUBBING SAID GASEOUS PHASE OF STEP (C) WITH AT LEAST A FRACTION OF LIQUID PHASE OF STEP (D) TO OBTAIN A SCRUBBED SUBSTANTIALLY PURE CARBON DIOXIDE AND HYDROGEN SULFIDE. |
