Q & A > Question Details
In our TGTU section of SRU, We have Stripper column which strips out H2S from the amine. The H2S will routed to SRU as feed from the Reflux drum O/H of Stripper Column. In recent days, it has been found that, all of Sudden Stripper Column level is decreasing and the same time The reflux drum get full and get overflow in the Overhead line(O/H). During this time there is a sharp increase in column PDI.
After a while, everything gets Normal after taking some actions (Reboiling steam cutting, reducing amine circulation rate,increasing reflux flow etc..,). This case happens rarely but we couldn't stop it.
What could be the reason for the above case. How to avoid it?
 
Answers
29/01/2019 A: Ravi shankar, HPCL, prskreddy@hpcl.co.in
1)Check if Your Amine might be foaming .
2)Check for Low amine H2s Loading or Operating load near turndown.
3)Check for column flooding.
4)Tune your reboiler steam c/v.
21/01/2019 A: Bruce Carr, Suncor Inc, bcarr@suncor.com
I agree you are definitely flooding.... but reading your actions I think you are going about it wrong..... If it is flooding and you have more than a few trays flooded and you cut the reboiler rate too fast you are running the risk of collapsing the trays..... Yes you should be reducing the feed to the tower but you should be reducing your reflux rate, letting it unload from the top.....
If the tower operates normally most of the time, its probably not an internal problem but rather you are passing the incipient flood point with too much reflux..... look at the differential temperature (DT) from top to bottom of the tower... you want maximum DT.... If you trend back I'm sure you will find the DT dropping and probably you were off spec which prompted the operator to increase reflux... you passed the incipient flood point which will just snowball.... Another sure indication would be the duty of the reboiler will drop while increasing reflux rate.....
21/01/2019 A: NS Murthy, Suez, murthy.ns.ext@suez.com
Amine tower in TGTU operates in one of the toughest environments. The quality of amine needs to be ensured to get hassle free operation. Check the quality of circulating amine (simply pH is a good indicator) for all its impurities present. Any degradation can even cause plugging of downcomers and trays / packing in the tower. Foaming of amine, if seen, it is time to reclaim the amine to get rid of impurities.
21/01/2019 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
Your stripper column is flooding. You probably want to have a tower scanning company out to do some scans to determine the cause. In the meantime you will need to limit rate to the unit to prevent flooding until the problem is fixed.
21/01/2019 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
Before commenting , I need to know where you are located.