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We have Cyclemax continuous catalyst regeneration in CCR, but it has been observed that regeneration gas flow to Regenerator FI reading goes low and on low flow Hot shutdown occurs. Its LP and HP tappings have been cleaned , but still it shows low flow. Can you please suggest what else could be the reason and how to resolve such issue??
 
Answers
29/03/2016 A: Peter Marsh, XBP Refining Consultants Ltd, peter.marsh@xbprefining.co.uk
If the LP and HP tappings of the regeneration gas flow indicator are clean and the problem persists, it may be due to problems with the nitrogen purge supply to the tappings. Perhaps the nitrogen purge flow indicator to one of the tappings is faulty or the nitrogen supply to one of the tappings has not been reinstated after cleaning?
Another possibility is that the inner screen in the burn zone may have become partially plugged with catalyst chips. This will cause the regeneration gas blower operating point to move back along its performance curve to a reduced flow corresponding to the increased system resistance. Have you checked the amps pulled by the regeneration gas blower motor and carried out a pressure survey across the regeneration gas loop to compare against baseline (start of run) data? If the screen is partially plugged, the CCR section can be shut down to enable the screen to be pulled for cleaning without shutting down the Platforming section.
20/03/2016 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
I hope you might have solved the problem by now. The low flow of the regeneration gas would effect the burn temperature profile adveresely. If that did not happen, the problem could have been with flow measurement device
11/11/2015 A: Amarjit Bakshi, Refining Hydrocarbon Technologies LLC, abakshi@rhtgulfcoast.com
It is assumed based on the question that actual flow is more than the FI shows ( and is as per the requirement of the licensor design operating manual) so there is shut down. If that is the case it is possible that there is some sort of blockage in the FI (orifice plate). Is it possible that some of the fine catalyst moves towards the FI and blocks it. When the regeneration gas starts through the FI as it is some what blocked and shows low flow due to blockage. Look into the option or send the P&ID and one can exactly troubleshoot the problem.