Patent ID: 7575725

Claim:
A catalytic reactor for the catalytic conversion of a feed stream by contact with fluidized catalyst particles to produce a product stream, said reactor comprising: a reactor section defining a catalytic reaction zone and a feed inlet communicating with the reaction zone; a separation section for separating gaseous products from fluidized catalyst particles, said separation section defining a particle outlet for discharging fluidized catalyst particles and said separation section defining a gas recovery outlet for withdrawing said gaseous products from the separation section; a disengaging conduit extending from the reactor section to the separation section, in fluid communication with the reaction zone, for conducting the product stream and fluidized catalyst particles and defining a discharge opening for discharging the product stream and fluidized catalyst particles; at least one catalyst circulation pipe for conveying fluidized catalyst particles to the reactor section, and a catalyst control valve on said circulation pipe for controlling the rate at which catalyst particles are added to the reactor section wherein said catalyst circulation pipe is in communication with the separation section; and a feed conduit for adding feed to said catalytic reaction zone; wherein said catalyst control valve is operable to control the space velocity in response to reaction conditions in the reactor.