摘要 |
The invention relates to a process for producing ammonia in a recycle circuit stream which comprises at least hydrogen, nitrogen and at least a portion of the ammonia formed as a product, characterized in that the ammonia is abstracted from the recycle circuit stream by means of a membrane unit. The invention further relates to an apparatus for producing ammonia in accordance with the process of any one of the preceding claims, said apparat us comprising at least a recycle circuit for allowing a recycle circuit stream to circulate, which recycle circuit effectively incorporates: a) at least one reactor provided with means for producing ammonia starting from hydrogen and nitrogen; b) at least one membrane unit provided with a membrane which is permeable at least to ammonia; c) means for feeding a feed stream into the recycle circuit (stream); d) means for abstracting a product stream from the recylce circuit (stream); e) optionally one or more elements, known per se, of a recycle circuit for preparing ammonia starting from a nitrogen- and hydrogen-containing feed; said apparatus being characterized in that the membrane unit (b) is provided in such a way in the recycle circuit that the recycle circuit stream can be passed alo ng one side of the membrane present in the membrane unit; and in that the means (c) for feeding the feed into the recycle circuit are connected to the membrane unit (b) in such a way that the feed can be passed along the other side of the membrane present in the membrane unit before the feed is fed into the recycle circuit. |