Reactor system for saturated c3-c6 hydrocarbon dehydrogenation

A reactor system for catalytic dehydrogenation of saturated C3-C6 hydrocarbons, where the reactor system comprises:

• a reactor disengager;
• a reactor within the reactor disengager, where the reactor comprises a reactor zone;
• a catalyst riser in fluid communication with the reactor at an upper end of the catalyst riser and in fluid communication with a regenerated catalyst stripper and a steam source at a lower end of the catalyst riser;
• and
• an exit riser in fluid communication with an upper end of the reactor, the exit riser in fluid communication with
• at least one cyclone adapted to separate catalyst from reactor effluent;
• where:
• the reactor comprises a lower portion thereof that is open to the reactor disengager and not hard coupled to the at least one cyclone;
• the reactor has a length and a diameter and the ratio of length to diameter ranges from about 1:1 to about 5:1.

A method for catalytic dehydrogenation of saturated Cx hydrocarbons comprising:

• feeding saturated Cx hydrocarbons and dehydrogenation catalyst to a reactor within a reactor disengager, where the reactor comprises a reactor zone comprising a lower portion thereof;
• dehydrogenating the saturated Cx hydrocarbons in the presence of the dehydrogenation catalyst to give a reactor effluent feeding through an exit riser to at least one cyclone;
• separating dehydrogenated product from spent catalyst in the at least one cyclone;
• flowing the spent catalyst down an annular space between the disengager and the reactor to a spent catalyst stripper and a catalyst regenerator;
• where the lower portion of the reactor is open to the disengager and in fluid communication with the annular space, and the method further comprises controlling the amount of catalyst within the reactor by varying the level of catalyst in the annular space.