5 replies to this topic

[raanii89]

Hi,

 

Currently I am in my final year doing chemical engineering.Were a given a project to design a styrene plant.We are required to do manual calculation and also simulation.

 

Is there any spreadsheet for material and energy balance of fractional distillation column?I have difficulties to draw x-y graph (ethylbenzene-styrene) to find no of plates as the boiling points of this two components are very near..Is there any ways to separate two components which have almost similar boiling point.

 

How to reduce no of plates fr this column.

[Mirco]

  hi raanii have you try to increase reflux ratio? in this way you may reduce the number of trays. Alternatively you may reduce operating pressure,this will increase relative volatility of components and the effect is the same,but it is a much more expensive solution.

[Bobby Strain]

The two components are easily separated at low pressure.

 

Bobby

[raanii89]

Thank you.

[Ahsan67]

hi,
i suppose you are talking about azetropic distillation, if is the case try to find the solvent which is able to absorb one component of your feed then mix it with your feed & then try to seperate them via other method that may not be distallation, what i am talking about that may be extraction or some other. or kindly share there boiling points, if it is not a azetropic distillation u can use phensky, & underwood equation to find min no. of plates & min reflux, the method you mentioned is mecab-theal for this you need the K values at each stage or you have to decide earlier the top & bottom temp . i also suggest you to use hysys for this.


Regards
Ahsan

[thorium90]

Ahsan, ethylbenzene and styrene separation is not an azeotropic distillation. Also, I believe you are referring to the method know as FUG method, or Fenske Underwood Gilliland method to designing a distillation column.
The graphical method the OP is referring to is known as McCabe Thiele method, of which a link to a spreadsheet created by Samir Khan I posted a while back can be found in this forums or by google.
K values, for relative volatility is technically not a needed value but a calculated value.
Component normal boiling points can easily be found on nist website.
 
To the OP, the following article may be of your interest
http://www.google.co...tents/US5386075

 

Edit: Attached the file by Samir Khan.

Attached Files

•  Binary Distillation McCabe Thiele.xlsx   39.44KB   146 downloads

Edited by thorium90, 22 June 2013 - 11:33 PM.