| 摘要 |
The invention concerns a process for the separate recovery of ammonia substantially free from carbon dioxide and water and of carbon dioxide substantially free from ammonia and water from a mixture of, substantially, ammonia and carbon dioxide, in which process: an ammonia off gas substantially free from carbon dioxide and water is separated from a mixture of ammonia, carbon dioxide and possibly water in an ammonia separation zone comprising a distillation or rectification zone (3) and the remaining liquid phase, which contains ammonia, a carbon dioxide and possibly water, is removed from the ammonia separation zone and fed to a carbon dioxide separation zone; a carbon dioxide off gas substantially free from ammonia and water is separated out in said carbon dioxide separation zone comprising a distillation or rectification zone (18) and the remaining liquid phase, which contains ammonia, carbon dioxide and possibly water is removed from the carbon dioxide separation zone, and water or an aqueous solution is fed to the carbon dioxide separation zone. To improve the efficiency of the process it is characterized in that the liquid phase removed from the carbon dioxide separation zone is fed to a first desorption zone (10) in which a gas mixture consisting of, substantially, ammonia, carbon dioxide and water and a dilute solution of ammonia, carbon dioxide and water are formed, which dilute solution is in part fed to the carbon dioxide separation zone and in part to a second desorption zone (22), in which second desorption zone virtually all ammonia and carbon dioxide are desorbed from the dilute solution to form, on the one hand, a gas mixture consisting of, substantially, water, ammonia and carbon dioxide and, on the other, virtually pure water. |
