Monitoring your particle size on your 3rd stage separator fines is still the best & “earliest” detection method for regenerator cyclone failure. On the reactor side putting your centrifuged fractionator btms under a microscope with picture taking capability will clearly show “round” cat. particles (much different than the irregular coke particles) and can be easily tracked for increasing amounts within a photo range.
If your 3rd stage increased recovery displays smaller than normal size particles check for
‘jetting” velocitiesfrom yur steam purges, torch oil nozzles, & air distributor.