Catalyst regenerator for catalytic cracking unit - has internal separator cyclones connected by standpipes to external gas plenum

摘要

A catalyst regenerator has an upright cylindrical chamber accommodating adjacent its upper end two or more separator cyclones each communicating via a nominally vertical metal standpipe with a plenum which is located exteriorly of the chamber and receives flue gas from the cyclones, the standpipes having insulating coatings thereon and extending through the top wall of the chamber and being secured by hanger to fixed structural supports externally of the chamber. The regenerator may serve a fluid catalytic cracking unit. The standpipes provide for conventional support of the cyclones, the hangers accommodating expansion and contraction of the standpipes. The external location of the plenum minimises thermal stressing thereof. The cracking unit disclosed includes upflow reactors discharging into a catalyst disengager from which spent catalyst is delivered to a coaxial regenerator chamber via a conventional stripper and valve, the catalyst being recycled to the reactors from a dense bed in the bottom of the chamber via further valves.