How to improve heat transfer with agitator at an asphalt tank? 1

[ultrazero]

Hello, all!
I am working on improving the heat transfer of hot oil heating coils inside an asphalt tank, at 100-ft in dia. The tank has 4" insulation, with internal solid fin heating coils, and no agitators. It not heated until the content needs to be offloaded to trucks. It takes 5 days to raise the tank temperature to 290F with 450F hot oil. One idea is to install two or three side mounted agitators to stir the content for better heat transfer, hence shorten the heat up time.

Please comment if you have experience, heat transfer equations or other solutions to this problem.

Thank you.
Ultrazero

 

[CARF]

Hi,

Agitation will improve heat transfer. Look for Helix type agitators, these are for very viscous fluids. What you could do as well is circulate over the tank with pump capable of handling the viscous stuff. This will improve mixing and thus heat transfer as well.

http://www.coleparmer.com/catalog/0304_pdf/A-1047.pdf

Good luck,