Vaccum residue IBP
Vaccum residue IBP
(OP)
Hello.everybody..
The vaccum crude distillation unit is having two similar trains of similar capacities and processing the same crudeblend with the same operating window.Now the question is how do one should structurally analyze the difference in the variations in the IBP of Vaccum residue produced from vaccum column bottom.
You can refer the graphical trend run chart of VR IBP for ready reference.
http:// files.engi neering.co m/getfile. aspx?folde r=2a9e32d7 -22e9-4ff4 -bf1f-29a1 c7605983&a mp;file=Ru nchart_of_ VR_IBP.ppt
with warm regards,
The vaccum crude distillation unit is having two similar trains of similar capacities and processing the same crudeblend with the same operating window.Now the question is how do one should structurally analyze the difference in the variations in the IBP of Vaccum residue produced from vaccum column bottom.
You can refer the graphical trend run chart of VR IBP for ready reference.
http://
with warm regards,





RE: Vaccum residue IBP
The difference cannot originate from bad sampling, I am sure about this. What I can think of is:
1. Bad control of wash oil flow rate
2. Thermal cracking of vacuum residue in the tower boot (high temperature, long residence time, unstable feed)
3. Poor control of vacuum system which causes high losses of distillates into the residue
What kind of system is it, wet or dry tower? With our without bottoms quench? COT? Feed type?
http://antwrp.gsfc.nasa.gov/apod/astropix.html
RE: Vaccum residue IBP
There are total 4 packed section – LVGO ,LVGO Circulation,HVGO & slopwax packed bed section.HVGO IR on below section is being maintained around 205 m3/hr ,It is damp vacuum condition i.e. 20 mmhg top section & around 32-34 mmhg vaccum at flash zone section.Yes,In the bottom VR quench flow is there to restrict bottom temp. around 354-360 C & Vaccum heater COT usually remains around 393 C .In the feed VR cut remains usually around 27 wt % & RCO feed to VDU section around 5-7 wt % 360 minus remains present usually.No much variations in column overhead or flashzone pressure.
with warm regards,
RE: Vaccum residue IBP
What is the change in 5% and 10% distillation points (is it ASTM D1160), if any? This can give you a clue - whether something is happening in the upstream ADU tower, or simply you have vey small (negligible) amounts of distillates in the residue that are lowering IBP without affecting/increasing overall residue yield.
Best regards,
http://antwrp.gsfc.nasa.gov/apod/astropix.html
RE: Vaccum residue IBP
with regards,
RE: Vaccum residue IBP
Dieselpet, Shalom.
As I see it the real enigma pops up in those cases when the IBP of the VR is lower than that of the HVGO. Your report covers from november to a week ago. Try to investigate what happened on those days on which the gap was wide and "normal" vs the other days. Include a possible "contamination" of the bottom quench stream from a leaking heat exchanger.
RE: Vaccum residue IBP
Did you employ any other method for VR distillation?
http://antwrp.gsfc.nasa.gov/apod/astropix.html