Q & A

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We are excited to be Strategic Partner of the World Refining Association’s ERTC: Ask the Experts. This new event from the organisers of ERTC, the biggest and most important event for the European downstream industry, is the only event in Europe offering process and maintenance engineers a platform to ask their burning questions about the everyday challenges facing their plant and hear the practical solutions from industry experts.

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
09/09/2020 Q: During precommissioning of our DHDT unit we want to pressurise the system with nitrogen by makeup gas compressor up to 50kg/cm2g. Can we increase pressure without achieving the minimum pressurisation temperature?
 
09/09/2020 Q: We have a sour fuel gas amine absorber where sour fuel gas from the refinery is treated with amine from the amine unit to strip out H2S. Sweet FG from the outlet of the absorber passes through a cooler then a filter coalescer to separate carryover amine from fuel gas. We are continuously getting water from the filter coalescer instead of amine. We have checked the cooler for tube leakage but no leak is observed, also the pressure of the fuel gas side is 0.5 - 1kg/cm2 higher than the cooling water. After checking the strength of a coalescer boot sample, almost 99% water is found. Is this a normal outcome or what are the probable causes of water formation instead of carryover amine?  
08/09/2020 Q: We have a reboiler whose shell was uninsulated. After insulation, I want to calculate the energy saved (heat saved). Temperature on the reboiler shell surface is ~155oC; on the insulation it is 40oC. Glass wool insulation is installed.  
03/09/2020 Q: In our Vacuum gas oil fractionation column, we have a diesel draw chimney tray. It doesn't have any overflow lines; the pumparound and internal reflux to the bottom trays of the chimney are provided by diesel draw pumps. I just want to know, if both our pumps had issues and stopped, how does liquid from the chimney tray reach down? Even though the liquid level reaches the chimney tray vapour ports, the liquid can't reach below the chimney tray through the vapour ports as the pressure of vapour flowing through the chimney tray vapour ports is more than the liquid pressure. Am I right? If the liquid can't travel down the chimney tray, the bottom trays becomes dry as the liquid flow from the chimney tray is stopped. In such cases, what could happen to the fractionation column top and bottom sections?  
01/09/2020 Q: Could you please share your experiences and strategy regarding reprocessing light coker slop? I am interested in a dosing strategy when the tank for light coker slop should be filled by off-spec products during DCU unit start-up only or in case of upsets in the DCU unit; during normal DCU operation light slop should be sent back for reprocessing on the DCU and the tank will be empty till the next shut down.
Do you perform some laboratory analyses to optimize the dosage rate of polymerization additive into the light slop?
 
Recently Answered Questions
Date  Replies
25/10/2018 Q: At a compressor's steam turbine, frequent vibrations are faced at Journal bearings. The vibrations go from normal 13microns to about 45 microns. Steam temp and pressure are normal We previously faced oil charring issue at the bearings and the problem was rectified by applying nitrogen in the seal. We suspect that the same problem has reappeared. Can anyone suggest how can we confirm if this is oil charring and how the issue can be resolved? (3)
07/05/2020 Q: How can we separate xylene (O, P and M) at 99% purity from reformate which is intended for making MS product.
Can it be done through distillation or does it require an extraction process in the aromatic solvent unit? What is the process called? Is there anywhere in India it is being done?
(4)
15/08/2020 Q: During processing of high TAN crude oils in a crude distillation unit generation of organic acids can occur. At what minimum value of TAN can these organic acids be generated during processing? Is there any rule of thumb for this ? (3)
30/07/2020 Q: In our hydrogen generation unit, a waste heat boiler functions to recover reformer O/L heat to produce HP steam. Boiler is single pass shell and tube exchanger with fixed tube. Since last year the boiler is not able to recover heat upto expectation as indicated by the raised process gas O/L temperature. The process gas O/L temperature is now around 288oC instead of 265 oC earlier. In the last 2 shutdowns the tubes have been cleaned thoroughly from inside but no benefit observed. Now it is suspected that there is fouling (maybe of silica) on the shell side. There is no provision to open and clean the shell side assembly. Is there is any technology available for online removal of such fouling (maybe some kind of chemical cleaning)? (1)
25/07/2020 Q: Why is furnace oil for burners blended with diesel? (3)
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