| 摘要 |
<p>PCT No. PCT/JP79/00192 Sec. 371 Date Mar. 24, 1980 Sec. 102(e) Date Mar. 5, 1980 PCT Filed Jul. 24, 1979 PCT Pub. No. WO80/00343 PCT Pub. Date Mar. 6, 1980. In the process for urea synthesis, an effluent from a reactor 2 containing urea, ammonium carbamate, excess ammonia and water is introduced in a first heater 3 to separate excess ammonia and to decompose ammonium carbamate, thereby separating them from the liquid phase; then the liquid effluent from the first heater 3 is introduced in a second heater 6 to separate the remaining excess ammonia and to decompose ammonium carbamate in the presence of starting carbon dioxide used as stripping gas, thereby separating them from the liquid phase; the liquid effluent from the second heater 6 is introduced into a urea solution purification step in which pressure is lower than in the above step; and the separated gaseous effluents from the first and the second heaters are returned into the reactor.</p> |
