| 摘要 |
In the present invention, there is disclosed a process for the preparation of ammonia at elevated pressure and temperature in an ammonia reactor (4), comprising passing a process stream (36) of ammonia synthesis gas successively through at least three catalyst beds (24, 26, 28) and reacting the synthesis gas in the beds; intermediately cooling of partially reacted synthesis gas (37) leaving the catalyst beds by heat exchange in heat exchangers (30, 32) arranged between each catalyst bed and withdrawing a product effluent (38) being rich in ammonia, wherein the process stream (36) is obtained by combining prior to introduction into the first catalyst bed (24), a first feed stream (6) of synthesis gas having been preheated through indirect heat exchange during the intermediate cooling of the partially converted synthesis gas (37), a second feed stream (8) of synthesis gas having been preheated by indirect heat exchange with the product effluent (38), and a third feed stream (10) of synthesis gas serving for adjustment of temperature of the process stream (36) and wherein the first feed stream (6) is passed successively through the heat exchangers (32, 30) for cooling the partially converted synthesis gas (37). Apparatus further comprises a feed-discharge means (34) arranged at the outlet of the third catalyst bed (28), whereby all the catalyst beds (24, 26, and 28), all the heat exchangers (30, 32) and the feed-discharge means (34) inclusive of connecting pipes are arranged within a pressure shell (12). |
