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Recent Questions
Date  Replies
19/01/2019 Q: 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?
(4)
19/01/2019 Q: Emergency Depressurization (EDP) System design
Our Hydrocraker unit has two emergency depressurization systems : 7 bar/min (100 psi/min) and 21 bar/min (300psi/min).
Unit design pressure is 160 barg and feedrate is 86 m3/h
Licensor assumes that EDP system (RO + Valve) is designed to decraease pressure unit by 7 bar or alternatively 21 bar in first minute .
Today unit is operated at higher flowrate (128 m3/h) and lower pressure (145 barg)
A depressuring test done in the new conditions showed that the depressuring rate decreased at 18 bar/min instead of 21 b/min in first minute.
Is this new depressusing rate still acceptable or should EDP valves and Restriction Orifice be resized to target 21 bar/min?



(1)
18/01/2019 Q: I have a problem with time consumed in purification through distillation. My distillation column consists of 27 feet 12" column with paul rings as packing components.
I have a reflux at 17 feet in column, that comes from the two condensers of 17 meter square and 10 meter square. I do distillation by two stage water ring vacuum pump with booster attached. I get the vacuum of 735mm/Hg.
What should be the reflux temperature that goes back in column? Or in reverse, what should be the temperature difference that goes back in column and at the bottom?
 
11/01/2019 Q: While buying and processing Eagle Ford crude oil from Texas, a large amount of methanol was discovered in Light Naphtha (About 700 ~ 800 ppm). Methanol was expected to be mostly removed from the Desalter, but after checking the samples at the front and rear of Desalter, the reduction rate was around 10%. The Desalter temperature and pressure conditions have been checked, but the phase may not be changed. Can you explain why methanol is not removed? (1)
10/01/2019 Q: Methanol content of Light Naphtha (<75) increased rapidly during processing. When I looked up the cause, I found that the oil produced in Eagle Ford of TX was high in methanol content. Methanol was expected to be removed in desalter, because it is polar solvent. However, the rate of elimination was 20 percent and very low than expected(in 2 stage Desalter).Why isn't methanol removed from Desalter? I would appreciate it if you could tell me the similar experience or literature. (1)
Recently Answered Questions
Date  Replies
19/01/2019 Q: 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?
(4)
19/01/2019 Q: Emergency Depressurization (EDP) System design
Our Hydrocraker unit has two emergency depressurization systems : 7 bar/min (100 psi/min) and 21 bar/min (300psi/min).
Unit design pressure is 160 barg and feedrate is 86 m3/h
Licensor assumes that EDP system (RO + Valve) is designed to decraease pressure unit by 7 bar or alternatively 21 bar in first minute .
Today unit is operated at higher flowrate (128 m3/h) and lower pressure (145 barg)
A depressuring test done in the new conditions showed that the depressuring rate decreased at 18 bar/min instead of 21 b/min in first minute.
Is this new depressusing rate still acceptable or should EDP valves and Restriction Orifice be resized to target 21 bar/min?



(1)
17/07/2018 Q: In our Refinery, we are facing continuous emulsion and water carry over from wash water tower. What all can be the reasons? (6)
10/01/2019 Q: Methanol content of Light Naphtha (<75) increased rapidly during processing. When I looked up the cause, I found that the oil produced in Eagle Ford of TX was high in methanol content. Methanol was expected to be removed in desalter, because it is polar solvent. However, the rate of elimination was 20 percent and very low than expected(in 2 stage Desalter).Why isn't methanol removed from Desalter? I would appreciate it if you could tell me the similar experience or literature. (1)
11/01/2019 Q: While buying and processing Eagle Ford crude oil from Texas, a large amount of methanol was discovered in Light Naphtha (About 700 ~ 800 ppm). Methanol was expected to be mostly removed from the Desalter, but after checking the samples at the front and rear of Desalter, the reduction rate was around 10%. The Desalter temperature and pressure conditions have been checked, but the phase may not be changed. Can you explain why methanol is not removed? (1)
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