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What can be the reason of higher CCR catalyst dusting rate (elutriation and dust removal is working properly)? Which part of the reactor can be failed if only catalyst dust was found in reformate?
 
Answers
15/05/2019 A: Mohan Pathak, UOP A Honeywell Company, mohanspathak@gmail.com
If the catalyst dust (not whole catalyst pills) is found in reformate stream only, then it indicates that there is severe dust formation in the regenerated catalyst lift line. Check the regenerated catalyst lift line alignment. Monitor the regenerated catalyst lift gas flow (mainly primary gas flow rate).
26/07/2018 A: Peter Marsh, XBP Refining Consultants Ltd, peter.marsh@xbprefining.co.uk
If you have an atmospheric CCR, leaking vent valves can cause cascading valve damage which increase catalyst attrition rates. In all types of CCR unit, excessive lift gas rate or incorrect installation of Dur-o-lok couplings in the lift lines will cause increased catalyst attrition. On the reactor side, if your unit is quite old and/or has suffered excessive thermal cycling, fatigue failure of the centrepipe profile wire to support rod attachment welds can lead to internal loss of catalyst containment (especially in the last reactor). Similarly, partial blockage of catalyst withdrawal scoops/funnels or catalyst transfer pipes with mechanical debris such as expander ring support lugs will increase catalyst attrition.