Process and apparatus for cracking ammonia

Apparatus for cracking ammonia comprising:

• a first adiabatic reactor for partially cracking heated ammonia gas at super-atmospheric pressure, the reactor comprising an inlet for heated ammonia gas, a catalyst bed having an upstream end in fluid flow communication with the inlet and a downstream end in fluid flow communication with an outlet for intermediate partially cracked ammonia gas;
• a further adiabatic reactor for cracking heated intermediate partially cracked ammonia gas, or heated intermediate partially cracked ammonia gas derived therefrom, the reactor comprising an inlet in fluid flow communication with the outlet of the first adiabatic reactor, a catalyst bed having an upstream end in fluid flow communication with the inlet and a downstream end in fluid flow communication with an outlet for partially cracked ammonia gas;
• a furnace comprising:
• a radiant section comprising at least one inlet for fuel and oxidant gas in fluid flow communication with at least one burner, catalyst-containing reactor tubes having upstream ends in fluid flow communication with the outlet of the further adiabatic reactor and downstream ends in fluid flow communication with an outlet for cracked gas;
• and
• a convection section in fluid flow communication with the radiant section comprising an outlet for flue gas,
• a first heat exchanger for heating ammonia gas by heat exchange with flue gas in the convection section of the furnace, the first heat exchanger comprising an inlet for ammonia gas and an outlet in direct fluid flow communication with the inlet of the first adiabatic reactor,
• a second heat exchanger for heating intermediate partially cracked ammonia gas by heat exchange with flue gas in the convection section of the furnace, the second heat exchanger having an inlet in direct fluid flow communication with the outlet of the first adiabatic reactor and an outlet in fluid flow communication with the inlet of the further adiabatic reactor,
• wherein the first heat exchanger is located upstream of the second heat exchanger within the convection section of the furnace relative to the flow of flue gas.