catalyst cary over from fccu fractionation tower
catalyst cary over from fccu fractionation tower
(OP)
hi
in our fccu we are facing with catalyst deposits in equipments downstream of the fractionator.the catalyst seems to be caried over to the the fractionator maybe due to the defficiency of the reactor cyclones . however the caried catalyst is supposed to be catched in fractionator by internal refluxes and enter the slury oil at the botum of the tower but as the unit is runing below 60 % capacity ther is a beleive that the tower internal refluxes are not mainained properly and so can not absorbe the entrained catalyst to downflow to slury oil . please let me know the coment on the mater and if any solution .
in our fccu we are facing with catalyst deposits in equipments downstream of the fractionator.the catalyst seems to be caried over to the the fractionator maybe due to the defficiency of the reactor cyclones . however the caried catalyst is supposed to be catched in fractionator by internal refluxes and enter the slury oil at the botum of the tower but as the unit is runing below 60 % capacity ther is a beleive that the tower internal refluxes are not mainained properly and so can not absorbe the entrained catalyst to downflow to slury oil . please let me know the coment on the mater and if any solution .





RE: catalyst cary over from fccu fractionation tower
Have you analysed the material to confirm that it is really FCCU catalyst and no some other material (i.e., a precipitate) that looks similar?
Good luck!
Bob
RE: catalyst cary over from fccu fractionation tower
thank you for your reply
we analysed the presipitated material , mostly they are catalyst whereas the catalyst content of slurry oil from bottum of fractoinator is less than 0.2 which is normal . again the question is ; how the bad performance of the tower ( when runing below the turn down capacity ) can cause catalyst cary over to overhead system ?
thanks
RE: catalyst cary over from fccu fractionation tower
1. try increasing reactor press as much possible
2. check rx stripping steam or any inadvertant steam entry
2. increase slurry recycle or wash liquid to maximum
May help
RE: catalyst cary over from fccu fractionation tower
By increasing the reactor pressure, we'd induce more catalyst circulation. This enhances attrition and the production of fines. This what we wish to avoid, don't we ?
RE: catalyst cary over from fccu fractionation tower
RE: catalyst cary over from fccu fractionation tower