Catalyst flow dampener

A flow dampener for converting a periodic discharge of a measured volume of catalyst particles from a moving bed system to a substantially steady particle flow rate which comprises:

• a cylindrical vessel containing a pair of chordal form catalyst passageways defined by the peripheral side-walls of said vessel and a pair of spaced apart chordal baffles disposed on opposite sides of a plane containing the central axis of said vessel and parallel thereto;
• a central catalyst hold-up chamber for receiving said periodic particle discharge and defined by said chordal baffles and the peripheral side-walls of said vessel which are not in common with said chordal-form catalyst passageways;
• the upper periphery of said chordal baffles being a finite vertical distance below the peripheral upper surface of said vessel;
• the lower peripheral surface of said vessel consisting of a horizontal plate attached to the lower periphery of said chordal baffles and extending between the lower periphery of said side-walls not common to said chordal-form catalyst passageways;
• said chordal baffles containing a plurality of horizontally opposed and vertically spaced apart outlet means, the horizontally opposed outlet means being sized to accommodate, in combination, up to about 50% of the average flow rate at which said catalyst particles are discharged into said catalyst hold-up chamber;
• and,
• said horizontally opposed outlet means being vertically spaced apart to provide a minimum particle hold-up volume between said outlet means substantially equivalent to the aforesaid measured volume of catalyst particles.