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Recent Questions
Date  Replies
31/08/2010 Q: I am working in a Diesel Hydrotreating unit. I would like to know how much should be the wash water flow.
I also look after Sour water stripping unit. Why are the feed valves to SWS stripper located near the tower.
Is there any specific reason for it? The same is the case with Amine recovery unit stripper. 		(1)
27/08/2010 Q: I would like to know in a plant that has different coolers that run off one cooling tower is it OK to pinch on cooling water when the cooling needs vary in different parts of the plant? I have worked in several different plants and this is usually an accepted practice but now I'm in a new plant and operators oppose pinching on the cooling water valves. Currently we are running cooling water at 90 degrees which in are second stage chiller I think is too hot and overloads the refrigeration unit but if we pinched cooling water at inlet discharge coolers and used compressors discharge temp to maintain our front in temp it would be a much better way to run the plant. (2)
15/08/2010 Q: we have an induced draft double-flow, cross flow cooling tower...using air to cool condensate water.
the tower fans has two speeds; low & high...In winter, usually low speed is used as the air temperature is low enough (Egypt), so that it reduces the water temperature by an acceptable manner. However; the water is found to exit from where the air enters -the louvers- while, through high speed operations in summer, this doesn't occur. 		 
11/08/2010 Q: What is the typical value of Hydrogen content in Coke for Resid FCC?  
11/08/2010 Q: What are the potential problems if feed remains un-vaporized because of heavy tail end of the feed? I know un-vaporized feed leads to increase in coke, which eventually burns in regenerator. Does anybody have any experience about how much portion of un-vaporized feed ends up in coke? Also in case of operating unit how one can figure it out whether feed is fully vaporized or not? (1)
Recently Answered Questions
Date  Replies
31/08/2010 Q: I am working in a Diesel Hydrotreating unit. I would like to know how much should be the wash water flow.
I also look after Sour water stripping unit. Why are the feed valves to SWS stripper located near the tower.
Is there any specific reason for it? The same is the case with Amine recovery unit stripper. 		(1)
04/06/2010 Q: we offloaded our CCR catalyst for reactor checks/repairs. we want to reload and I don't know the maximum permissible coke allowed on the used catalyst. Should we load catalyst with coke level of 6%wt? (3)
27/08/2010 Q: I would like to know in a plant that has different coolers that run off one cooling tower is it OK to pinch on cooling water when the cooling needs vary in different parts of the plant? I have worked in several different plants and this is usually an accepted practice but now I'm in a new plant and operators oppose pinching on the cooling water valves. Currently we are running cooling water at 90 degrees which in are second stage chiller I think is too hot and overloads the refrigeration unit but if we pinched cooling water at inlet discharge coolers and used compressors discharge temp to maintain our front in temp it would be a much better way to run the plant. (2)
31/10/2009 Q: Is there a heat transfer fluid that can withstand a temperature of up to 600 deg C plus? (2)
11/08/2010 Q: What are the potential problems if feed remains un-vaporized because of heavy tail end of the feed? I know un-vaporized feed leads to increase in coke, which eventually burns in regenerator. Does anybody have any experience about how much portion of un-vaporized feed ends up in coke? Also in case of operating unit how one can figure it out whether feed is fully vaporized or not? (1)
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