A new catalyst regenerator technology was developed to improve Δcoke operations. Since improved equipment technology and catalyst offerings have resulted in progressive decreases in Δcoke, refiners have continued to debottleneck unit constraints within the capacity of existing major equipment. Usually with the constraint of not replacing main vessels or large rotating equipment, i.e., main air blowers (MABs), wet gas compressors (WGCs), regenerator shells, reactor shells, stripper shells and catalyst circulation standpipes. Maintaining this philosophy through several technology upgrades can result in several operational and reliability concerns:
Excessive catalyst loading to regenerator cyclones
Cyclone erosion, fines generation
High catalyst circulation and catalyst flux
Insufficient regenerator and stripper residence time
Hydraulic instability or limitation in the catalyst standpipes
Excessive catalyst fines to the flue gas system
Increased particulate matter (PM) emissions.