Ammonia synthesis method
OwnerCornelius E. Shannahaninventor
Life of this patent
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Abstract
A process for producing ammonia by reaction of a hydrogen and nitrogen-containing synthesis gas in the presence of a solid particulate catalyst for the reaction, includes conducting the reaction at pressures significantly lower than that of conventional ammonia synthesis, e.g., at about 30 to 70 atmospheres, in a fluidized bed of the catalyst. The synthesis gas is used to fluidize the catalyst and the resultant fluidized bed is preferably maintained under substantially isothermal conditions, e.g., by flowing a coolant liquid in indirect heat exchange relationship with the fluidized bed. Suitable catalysts for the process include activated iron catalysts which may be of very fine particle size.
Claims19
A process for producing ammonia, comprising:
- (a) contacting a synthesis gas mixture comprising hydrogen and nitrogen with a mass of solid, particulate ammonia synthesis catalyst under conditions to fluidize the mass of catalyst, and maintaining the catalyst mass in a fluidized state by a fluidization step consisting essentially of controlling the volumetric hourly flow rate of gas through the fluidized mass, and the pressure within the reaction zone;
- (b) passing the synthesis gas through a reaction zone in contact with the fluidized catalyst mass;
- (c) maintaining the reaction zone at an elevated temperature and at a pressure of from about 20 to 100 atmospheres to therein react hydrogen with nitrogen to form ammonia and provide a reacted synthesis gas stream;
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- (d) flowing the reacted synthesis gas stream from the reaction zone to an ammonia recovery zone and therein recovering from the reacted synthesis gas stream ammonia produced in the reaction zone to provide an ammonia product and an ammonia-depleted gas.
A process for producing ammonia by reacting hydrogen and nitrogen in a synthesis gas in the presence of a solid particulate catalyst for the reaction, comprising:
- (a) contacting the synthesis gas with the catalyst in a reaction zone under conditions to maintain in said zone a fluidized catalyst bed by a fluidization step consisting essentially of (i) controlling the volumetric hourly flow rate of gas through the fluidized mass, and (ii) maintaining a pressure of from about 20 to 100 atmospheres in the reaction zone;
- (b) in said reaction zone, reacting a portion, but not all, of the hydrogen and nitrogen content of the synthesis gas to form ammonia;
- (c) withdrawing the resultant ammonia-containing, reacted synthesis gas from the reaction zone and separating ammonia therefrom to provide an ammonia-depleted synthesis gas and an ammonia product;
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- (d) recycling the resultant ammonia-depleted synthesis gas to the reaction zone and concurrently introducing fresh synthesis gas to the reaction zone.
Dependencies are inferred from the claim text.