5 replies to this topic

[gus.inspired]

Hi,

I have an agitated vessel with an external half pipe, and also internal coil. I would like to calculate the overall heat transfer coefficient. The tank contains paraffin wax (CAS number 8002-74-2). which must be kept at 135°C and the heating medium is saturated steam at 140°C.


1. how do I calculate the overall heat transfer coefficient?
2. do you have any ideas on how to improve wax melting in a batch operation (i.e. melt the wax faster, the wax cannot be heated above 140°C to prevent oxidation).

LBA

[ankur2061]

LBA,

For heat transfer coefficients for half-pipe coil jackets refer the link below:

http://www.cheresour...sel-design?pg=3

For heat transfer in helical coils refer the attachment with this post.

Regards,
Ankur.

Attached Files

•  Heat_Transfer_Coeffs.pdf   48.36KB   14388 downloads

[breizh]

Take a look at this paper , it should support your query.

Flakes should be easier to melt than block!

Most probably difficult to manage the temperature @ 135 C with saturated steam . I remember using Hot oil for such application (higher temp).

Breizh

Edited by breizh, 02 July 2012 - 07:53 PM.

[Shivshankar]

Hi

Also have a look at these examples, might be helpful.

http://www.engineeri...fer.html#jacket

Regards
Shivshankar

Attached Files

•  AGITATED%20VESSELS.pdf   848.28KB   8631 downloads
•  agitating vessel.pdf   4.04MB   7603 downloads

Edited by Shivshankar, 30 July 2012 - 08:29 AM.

[Chris Haslego]

Clarify something for us....do you already have this set up or are you trying to design this set up? I would share the previous referenced concern about using steam if there is temperature sensitivity. Hot oil or a pressurized water loop may be a better option.

[gus.inspired]

Hi Chris,

I am currently designing this set up. You are right, I have settled for hot oil in this system.