5 replies to this topic

[jigs1980]

We have stripping steam as well as reboiler for stripper to improve the flash point of the diesel. The flash point is not getting achieved while diesel production is more (i.e. 210 M3/hr), but the flash point improves, when diesel production is less (i.e. 160 M3/hr.). The steam is checked from drain and it is free from condensate. The stripping steam is also maximized, but no change in the flash point. The operating heat flux was calculated (i.e. 25000 W/m2). I think it is well below the allowable heat flux for thermosyphon reboiler. So, what could be the cause of poor stripping at higher load? 

[Bobby Strain]

You didn't really convey much information. So, start over and give us details on the operation. We have no idea what you are talking about when you say steam is checked from drain. What steam? What Drain? A sketch might help, too.

 

Bobby

[breizh]

Hi ,

Thanks if you share with us a P&ID together with information about the quality of the steam ( saturated , superheated ) and other parameters related to your operation and maybe the spec sheet of the thermosyphon .

 

 

Breizh

Attached Files

•  thermosiphon reboilers.pdf   235.23KB   29 downloads

Edited by breizh, 27 July 2018 - 08:06 AM.

[Technical Bard]

Agree you need to provide more detail - but I would be suspicious about column flooding at the higher diesel rates, and your reboiling/stripping steam may not be high enough.  They need to increase by the same amount as the throughput.

[gegio1960]

maybe you increase the diesel production by including too much light material (ie kero) in it.

[rdcrags]

What is the destination of the stripped diesel? Diesel hydrotreater? Tank and then hydrotreater? Tank, and then diesel blending system?