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Recent Questions
Date  Replies
15/07/2019 Q: Thanks a lot Mr. Sam Lordo for your Answer on below question , Please also enlighten me whether the water injection rate should be 1-2% of the total overhead flow based on the query below?
"In our distillation column we are treating Natural Gas Condensate with 76 ppm sulphur, Acidity < 0.05 mg KOH and organic chloride <0.3 ppm and water content < 0.05%. but designer did not keep any caustic, corrosion inhibitor and Ammonia dosing provision due to combat corrosion at overhead line. Also they did not keep any DM water flushing provision (for fouling control within the tubes of aero condenser). Is it ok not to keep above provision as per above spec of NGC or NGL? But we are draining the overhead drum water separating boot approximately 10-15 litres per day where PH remains 5 to 5.5. So, do we need to use NH3, Caustic and corrosion inhibitor in order to keep PH more than 6?"
14/07/2019 Q: Which metal is used for sulphur guard for naphtha services? What are the available options?  
13/07/2019 Q: At our Stripper Column Overhead of Naphtha Hydro-treating Unit , we are injecting pure Chimec 1044 (from CHIMEC S.p.A)which is a blend of polymeric compound in heavy aromatic solvent @ Injection rate kg/hr : 0.02 kg/h of pure Chimec 1044 based on 10 wt. ppm chemical injection rate over the process rate.

Besides, Natural Gas Condensate (NGC) is used as a feed for Natural Gas Condensate Fractionation Distillation Coulmn (CFU) which is a by product from Natural Gas Plant having very low sulfur as well as salt. In fact, we are planning to blend 5% TG with high sulfur (from other crude oil refinery) together with the NGC for processing in CFU .
Can i use the same Corrosion Inhibitor (Chimec 1044) at the overhead of our (CFU)?
28/06/2019 Q: I hv naphtha cracker wherein there is an issue of fouling in cracked gas compressor and it's intercoolers also. What is exactly the fouling material . Is it styrene and butadiene most of the time ? Customer is doing wash oil at 2 percent rate continuously and wash water with batch mode only . What is the role of wash oil? Wash oil can not act as antifoulant right ? Can you please explain. What are treatment options for fouling in such equipment ? Also let me know red oil formation in caustic tower ? What is composition of red oil ??  
28/06/2019 Q: For our Delayed Coker Unit after quenching drum some portion of hydrocarbon is coming from the vent lines while opening of the vents to continue draining. We checked the quench oil lines to be sure the valves are leaking but quench oil valves are not leaking. We tried to put steam by opening the steam connection just upstream of the vent valves during quenching. It helped but for this time, we have some problem with quenching of the drum. The drum overhead line is not cool down enough during quenching.
Can anyone help to identify reasons why hydrocarbon is coming from vent?
Recently Answered Questions
Date  Replies
27/06/2019 Q: How do you estimate the decrease in yields resulting from an increase in pressure in the fractionator due to fouling in the head coolers? (2)
24/05/2019 Q: We have a problem at our CDU. It is observed that when we examine salt content at the start of crude charging tank after giving it 24 hour settling time, salts are in yhe range of 2 to 5 PTB. But when same tank is charged and sample is taken at CDU upstream, salt content is higher... Up to 50bPTB... What could be possible reasons? (6)
23/06/2019 Q: We are facing problem of shorter run length of our Delayed Coker Unit(DCU). The furnace coil inlet pressure increases to design limit within a very short interval i.e. 30-35 days after the SAD, however the tube skin temp remains well below the design limit.
The feed to the DCU unit is VR from VDU, having asphaltene about 5% & CCR about 17%. The COT, BFW flow and other operating parameters are maintained as per the design operating guidelines.
Can anyone help to identify reasons for the drop in the run length of our DCU?
30/04/2019 Q: What is the best check valve type at reciprocating compressor discharge line on Hydrogen service? Also references of manufacturers for this type of check valve. (1)
01/03/2019 Q: In a naphtha stabilizer, top tray (tray 46) temperature is controlled by the reflux and the bottom tray (tray 3)temperature is cascaded with the hot light gas oil flow (reboiler's hot medium). Top pressure (overhead vapor pressure not the OVHD drum pressure) is controlled by the removal of non-condensed vapors from OVHD accumulator. Here, when I increase the bottom tray temperature, top pressure is getting increased slightly (very minimum) and then OVHD vapor pressure is getting decreased faster. Can anyone explain this phenomenon? Note: Distillation tower - 48 trays column; OVHD product - LPG; Bottom product - Stabilized naphtha. (4)