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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
11/09/2017 Q: In Hydrocracker fractionator, ATF draw temperature is 220 Deg C which is going to side stripper. Side stripper is having reboiler which is taking heat from diesel pump around. The reboiler outlet temperature is about 250 Deg C.It is observed that when the ATF draw increases beyond 50 M3/hr. it is failing in Flash while maintaining the temperature condition same. Column is operating at 2.1 Kg/cm2g pressure.
Where is the problem?
 
10/09/2017 Q: One of the PSU owners is asking for guarantees at the outlet of Propylene Recovery Unit (PRU). The basic design of this unit is in Consultant's scope. At present the poisons in feed such as Methyl Acetylene, Propadiene, Arsine, Phosphine and many others are not known. In fact feed composition is not known at all. However the poison levels in the product are fixed and are to be guaranteed. The propylene from PRU is routed to Polypropylene Unit. The feed to PRU comes from LPG treatment unit which in turn receives it from RFCC unit. Please advise whether it is wise to give guarantee of product at the outlet of PRU.  
08/09/2017 Q: I am working in UOP hydrocracker unit. In our feed filter backwash frequency is very high since one month. We have cleaned the filter elements one by one. After cleaning of filter some improvement seen for some days but then filter starts backwashing again. we have also checked CCR and asphaltene and all are within range. we process VGO and HCGO in our hydrocracker unit . It is recycle type with 97% conversion. please suggest remedy.  
05/09/2017 Q: How to control fractionator profiles in hydrocraker unit?  
05/09/2017 Q: What's cross limiting control in heater forced draft type. Why stoichiometric air and Wobbe index given in the calculations?  
Recently Answered Questions
Date  Replies
31/08/2017 Q: What are the normal metal contents in vacuum residue and coke? How does it affect the final price of the coke? (4)
22/08/2017 Q: I would like experts' comments on ATF processing. We don't hydroprocess LK to produce ATF. We only change the form of sulphur compounds in an alkaline solution in presence of air. The reactions proceeds as below
2R'SH + 2RSH +O2-> 2R'SSR +2H2O.
We have a constraint that while processing light slop in crude unit we cant ATF as it results in colour deterioration of the product. Can i get some expert comments as why this happens. and whether this method of producing ATF is followed elsewhere?
(4)
31/08/2017 Q: Radiant tube skin temperatures of CCRU preheter and interheaters has increased and nearing the design tube metal temperature of 625 Deg.C. Whether anyone has faced such issues in CCRU?
What is the solution to bring back the skin temperature to normal? It is to be noted that no decoking facility has been provided since the service is clean.
(3)
24/08/2017 Q: In our Diesel hydrotreater unit we faced an issue in heater steam coils.The steam outlet temperature was 230 before desuperheating and after desupheater more than 380 deg C . We injected boiler feed water to desuperheater to reduce the temperature but we absorbed temperature goes up even we closed boiler feed water.we checked all instruments it's good. What is the problem behind that and how to solve it? (2)
12/08/2017 Q: Decoking of the fired heater of VDU
During recent years , the skin temperature of one of the 4 coils developed a slightly higher skin temperature than the other 3 coils , the skin temperature is nearly 500 C , it is still in the safe range but we are now considering decoking to to remove any present coke during shutdown . Anyways , I am comparing SAD ( Steam Air Decoking ) to Pigging , There seem to be many hazards and incidents during SAD , i wonder if any of you witnessed any incidents with SAD ? ... Can anyone clarify the potential hazards and their severity ? do you recommend it or you recommend pigging ? ...... Thanks for your comments and replies in advance ....
(5)
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