| 摘要 |
The present invention is directed to a catalytic process for the synthesis of ammonia in an ammonia synthesis reactor wherein a dilute ammonia stream is withdrawn from the reactor and subjected to a treatment step to concentrate ammonia adsorbed (or extracted) from said dilute ammonia stream. Specifically, the invention is an improvement in the ammonia concentration treatment step. This improvement includes passing the dilute ammonia stream from the reactor into an adsorber in which is housed particulate adsorbent effective in adsorbing ammonia from the dilute ammonia stream passed through the adsorber. Desirably, adsorber conditions include a pressure close to those prevailing in the dilute ammonia stream withdrawn from the reactor with the temperature being as low as that of the feed to the reactor. Next, an effluent stream diminished in ammonia content is withdrawn from the adsorber. Finally, enriched ammonia is recovered from the adsorber. Such ammonia recovery from the adsorber may include a rinse step in which enriched ammonia is admitted to the adsorber while withdrawing unadsorbed feed from the interstices of the adsorber, conventional blowdown where ammonia is desorbed, a low pressure purge with recycled dilute ammonia stream, and re-pressurization of the adsorbent bed with additional recycled dilute ammonia stream so that the adsorber is in condition for reuse in the adsorbing step of the process. Desirably, multiple adsorbers operating in parallel are envisioned for use with the reactor in a continuous process.
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