Patent ID: 7611677

Claim:
A reactor system comprising a source of fresh or regenerated catalyst reactor of elongated shape along an essentially vertical axis, said reactor comprising a cylindrical shell and several vertically-staged catalytic reaction zones in said cylindrical shell, whereby said reactor is adapted to the axial circulation of a reaction fluid serially in each of said zones and comprises means ( 100 ) for introducing and means ( 101 ) for evacuating said reaction fluid, means ( 102 ) connected to said source of fresh or regenerated catalyst for intake of fresh or regenerated catalyst at the top of the reactor, and means ( 105 ) for evacuating spent catalyst in the lower portion of the reactor, said reactor comprising: an upper reaction zone ( 3 a ) filled with granular catalyst, at least a section of zone ( 3 a ) being vertical and diametrically coextensive to that of the cylindrical shell on a portion of its height, directly connected via a constriction zone to a reaction zone ( 3 b ) that is also filled with granular catalyst at least a section of zone ( 3 b ) being vertical and diametrically coextensive to that of the cylindrical shell on a portion of its height, located just below the upper reaction zone ( 3 a ), whereby said reaction zones ( 3 a ) and ( 3 b ) are two successive reaction zones that are directly connected by a reaction effluent path, and by a catalyst path from zone ( 3 a ) to zone ( 3 b ) through said constriction zone, whereby zone ( 3 a ) is connected at its upper portion, directly or indirectly, to said fluid means ( 102 ) for feeding fresh or regenerated catalyst, whereby zone ( 3 b ) is connected at its lower portion, directly or indirectly, to said means ( 105 ) for evacuating spent catalyst, whereby the reactor, placed at the constriction zone between this constriction zone and the cylindrical shell of the reactor, also comprises a heat exchanger ( 8 ) for heating or cooling reaction fluid circulating between zones ( 3 a ) and ( 3 b ), and means for transporting fresh and/or regenerated catalyst to said reactor.