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This face to face interactive event, features experts from leading European refineries and technology providers; engineers will have the chance to hear unparalleled knowledge through interactive discussions such as fishbowl panels, Q&A Panels and Poster Sessions. Learn more here: asktheexperts.wraconferences.com  


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Recent Questions
Date  Replies
08/10/2019 Q: Can someone explain what does the pressure ratio and the critical pressure ratio mean in the following link? Also, does anyone have an Excel related to steam silencer design?
https://www.geothermal-energy.org/pdf/IGAstandard/WGC/2005/1345.pdf
 
07/10/2019 Q: What are the alternatives to hydrojetting to clean heat exchangers in a refinery?

Are there any chemical cleaning solutions available to clean after bypassing the exchanger?

Thank you
 
07/10/2019 Q: I am currently working in Exxon Flexicracking FCC model. During start-up of the unit, when we establish catalyst circulation, sour water received in the MF O/H drum is acidic. When we introduce feed to the reactor, it becomes neutral. Why is it so? I am interested in the chemistry of the process leading to acidic boot water. Can we reduce the acidity by changing operating conditions of the MF or R-R section?  
07/10/2019 Q: I am currently working in Exxon Flexicracking FCC model. During start-up of the unit, when we establish catalyst circulation, sour water received in the MF O/H drum is acidic. When we introduce feed to the reactor, it becomes neutral. Why is it so? I am interested in the chemistry of the process leading to acidic boot water. Can we reduce the acidity by changing operating conditions of the MF or R-R section?  
05/10/2019 Q: Why is sour water from the main fractionator O/H drum acidic in the FCC during initial catalyst circulation without feed but becomes neutral after introducing feed to the reactor? I am interested in the chemistry of the process leading to acidic sour water? Are there any ways to reduce the acidity of sour water by changing the operating conditions of the reactor or fractionator?  
Recently Answered Questions
Date  Replies
20/10/2009 Q: VDU off-gases are being routed to LP flare header through a water seal drum (VDU ISBL). It has H2S content around 2 mol%. Is it possible to burn it in VDU furnace? Constraint is higher H2S content. Can we use water seal as amine seal to absorbe H2S?
Any other destination of these gases?
(4)
28/07/2016 Q: I am working as production Engineer in FCC block which consists of FCC and LPG Treater unit.
LPG treater treats cracked LPG from FCC and Delayed coker Unit.IT has capacity of treating 404 m3/hr.We are experiencing a peculiar problem these days. Our LPG is getting contaminated with light yellow colour at the outlet of LPG treater unit. LPG ex FCC and coker unit is clear and having no signs of yellowish colour but at outlet it is failing. Copper strip corrosion and weathering tests are absolutely fine.
The following are the observations --
1) These units are commissioned 6 months ago and we didn't come across DSO formation in DSO settler but LPG quality is ok (Probably due to low mercaptans load in LPG, DSO is not forming in the process)
2) The lean amine H2s loading in FCC & DCU LPG washing is around 1200 -2400 ppm. May be noted here that on earlier occasions with this loading of amine,the downstream treater unit was giving good LPG wrt all lab tests.
3)The only problem is with colouring with which we are struggling.
4) sometimes we experience yellowish colour at the unit inlet of LPG treater.Even at the outlet of FCC & DCU also.But the colour is not that much remarkable.But in treater outlet the pale yellow/dark yellow colour is visible upon complete evaporation of LPG.Sometimes 0.5 to 0.1 ml of yellow residue is left and sometimes not.
5) We took complete shutdown of unit, depressurised, all caustic drained from system and vessels and fibre film contactors were water washed and again took the system inline but the yellowish colour in the system LPG still coming.The custic regenration is good and quality is good and copper corrosion test is ok.
The reason for yellowishness we unable to find out.
Can anyone share their experiences in dealing with this type of typical problem in MERICHEM section of caustic wash of LPG?
(6)
25/02/2018 Q: In FCC unit, Does PSD of the catalyst effect the catalyst loss through stack? (3)
26/09/2019 Q: Is there any alternative to caustic ( NaOH) addition after the desalter in the crude unit to control chloride carryover? As we know, sodium is the cause of fouling in the downstream unit with the addition of higher dosages of NaOH. Thank (4)
25/09/2019 Q: Sour water from the SRU quench column is routed to the sour water stripper normally.My doubt is whether this will go to the Phenolic Sour water Stripper or Non-phenolic sour water stripper? Request the professionals of SRU to clarify. Please also explain the reason if it is routed to the Phenolic Sour water stripper unit. (2)
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