4 replies to this topic

[gbgbhagavan]

Dear All,
 
I am presently designing bottom heating steam coil (bare tube) for RCO (reduced crude oil) or Asphalt service atmospheric storage tank. The tank is fixed roof, steam blanked. and insulated with rock wool.
 
Based on the relevant info. available from the Cheresources forum and D.Q. Kern book, I had calculated total heat loss and accordingly bare pipe dia and length required for making up the heat loss for a given insulation thickness.
 
Now, I have to select suitable layout (pattern, length of each side, outlet condensate size, etc.) for the bottom heating coil so that it can be given for fabrication. I request your help and guidance for this.
 
Thanks & Regards...

[Napo]

Dear Gbgbhagavan,

 

Maybe you can review the article "Designing Heating Coils for Tanks by Nomograph" of Julio Otazo, in "Chemical Engineering" Magazine or "Calculation&Shotcut Deskbook" published by Chemical Engineering, p. 106-107.

 

I hope this help you.

 

Regards,

 

Napo.

[gbgbhagavan]

Thank you very much dear Napo. Your post helped me a lot and I could get the nomograph. With the help of this, I will design the coil arrangement of standard type. Do you know of any other coil arrangements recommended for heavy oils like RCO/Asphalt? Also, could you clarify what is the small arc at one end of the steam coil?

 

I think it is ok to maintain same coil dia. through entire length of the coil without having to reduce the dia in view of steam condensation. I would like to suggest 1 in 200 as slope for coild to ensure positive condensate drainage and hope it would be alright.

 

Thanks & Regards.

[Napo]

Dear Gbgbhagavan,

 

You can review other types and recommendations in the same article reference: Perry´s Chemical Engineers´ Handbook, 4th. ed., 1963 (section 11, p. 21-23) or actually in Perry´s Chemical Engineers´ Handbook, 8th ed., 2008 (section 11, p. 21-22).

 

Best Regards,

 

Napo.

[gbgbhagavan]

I got it. Thank you very much, Dear Napo.