Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Lab Vacuum Distillation

Lab Vacuum Distillation

Lab Vacuum Distillation

We are due to start up a Vacuum Distillation unit shortly, and I am seeking advice on the best laboratory testing method to follow our operation (feed plus products) and equipment for vacuum distillation, namely advice on whether to choose ASTM 1160 or ASTM 5236 (or other), plus recommended suppliers of the equipment.


RE: Lab Vacuum Distillation

The best method today is 'simulated distillation' by gas chromatography.  Both standard and 'high temperature' methods are widely used and accepted. These produce highly repeatable distillation curves quite quickly(45 min). However, they do not produce the various fractions needed for determination of the cut properties.

For moderate size 'cuts' , the 'spinning band' method and apparatus gives fast, repeatable, and accurate fractionation into cuts from light ends to heavy vacuum gas oils in about 6 hours using 250ml of sample.

Large scale (more than 500ml) of cuts forces one into D1160 type apparatus and the attendant imprecision and poor fractionation. Alternatively,  TBP (true boiling point) apparatus can be used wit hhigh reflux ratios and theoretical stage count to achieve high separation efficiencies and sharp cuts, but the procedure is time consuming and therefore costly.  

In any of these methods, expertise in reviewing and analysis of the data is essential.Lots of 'deep cut' vacuum distillation designs failed to work as expected because process engineers failed to understand and appreciate (respect) the limitations of th etest methods.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close