Q & A > Question Details
Have anyone use platforming continuous catalyst circulation technology experience catalyst plugged in the bottom of Reforming reactor after turnaround? What may inhibit the catalyst flow to the regeneration section from bottom of reactor (catalyst collector)?
08/06/2018 A: naveed bilal, Pak-Arab refinery Limited, naveedbilal@yahoo.com
For Catalyst Plugging/Blocking problem/ issue in lifting problem, you should check/correct one of the following Parameters:
1) Purge Gas Temperature & Flow, they should be within design limits.
2) Primary and Secondary lift gas flow a & their flow meters calibration.
3) Proper Sulphur (DMDS) dozing rate.
4) Proper Insulation of Lift Line & Reactor Bottom (Catalyst Collector).
In which season you faced the Problem (summer/Winter)?
30/04/2018 A: Muhammad Akhtar, Orpic, mbadgk@gmail.com
Whether the Platforming Reactors were opened during turnaround,
if Yes, than it is mainly due to external material plugging. Most probably due to insulation material or some gaskets etc.
If no, then most probably the condensation of liquid in the bottom portion leading to agglomeration of the catalyst in the legs.
03/01/2018 A: Peter Marsh, XBP Refining Consultants Ltd, peter.marsh@xbprefining.co.uk
You don't say whether this is a UOP or Axens type unit. I will assume UOP. Are you sure that the blockage is at the bottom of the stacked reactors? If so it could be a physical blockage such as construction debris blocking catalyst withdrawal funnels or it could be a problem with purge gas flow or temperature (too high a flow may cause catalyst hangup, too low a temperature may cause condensation of the reactor effluent stream making catalyst pills "sticky").
Have you considered that there could be a blockage within the Lift Engager (Atmospheric or Pressurised CCR) or L-Valve (Cyclemax CCR) or that primary and secondary lift gas flow meters may have been incorrectly calibrated? Have you considered that valve internals on Lift Engager inlet or outlet isolation valves may have separated from the valve stem such that the PLC logic thinks the valve is open when it is actually closed?