Q & A > Question Details
Is it possible to reduce reactor stripping steam ring steam flow below minimum, if min dP criteria is passing? This is to increase regenerator dense phase temperature as we are not able to make required coke.
22/02/2016 A: Eric Hennings, Technip Stone & Webster, EHennings@technip.com
Best practice is not run stripping steam below minimum turndown of the steam distributor. Otherwise, mechanical damage can occur.
Lowering stripper efficiency (with less steam) is generally unfavorable as valuable products will be burned as coke.
Assuming that increased coke make is desired to help the heat balance, consider adding coke precursors to the feed.
If the coke deficiency is more or less permanent, then consider a minor revision to steam distributor during turnaround.
24/09/2015 A: Sudhakara Babu Marpudi, Dangote Oil Refinery Company, m_sudhakarababu@yahoo.com
One should be wary of the effects of condensate in the stripping steam. Reducing stripping steam to theoretical levels can probably lead to condensation. One failed steam trap has resulted in pulgging of the steam dispersion nozzles, leading to higher velocities in the remaining nozzles, erosion and through and through hole on the reactor shell. Catalyst poured out of this hole. I guess stripping steam is more useful for recovering the hydrocarbon vapor trapped in the dead zones under the stripper baffles of the reactor ( enhancing product recovery ???).
24/09/2015 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
Not a good solution because you will be burning hydrocarbon. Best solution is to increase feed preheat temperature, assuming your unit has a feed preheater.