4 replies to this topic

[Ashokk]

We have Naphtha Stabilizer column in Our CDU/VDU unit which treats the CDU OVHD Product and separates it into LPG and Naphtha. LPG getting more C5 components than required percentage. To resolve this operators decreased the reboiler duty and tried increase the pressure of the column. How these parameters impacts the C5 seperation?

 

[Nikolay_]

Hi, fugacity C5 is decreased when pressure increases. So oprerator, perhaps, tries to increase top pressure by increasing reflux temperature with reflux flow adjustment but not heating up bottom.

Edited by Nikolay_, 02 March 2026 - 06:23 PM.

[Ashokk]

Hi, fugacity C5 is decreased when pressure increases. So oprerator, perhaps, tries to increase top pressure by increasing reflux temperature whith reflux flow adjustment but not heating up bottom.

Can you give me more detailed answer?

what my understanding is by increasing the pressure the heavier hydrocarbons in the overhead line turns into liquid inside the column with that they can maintain the quality of the product.

[Nikolay_]

The higher the pressure, the harder it is for C5 to rise to the top of the column.

[rabindrawithu]

The correct approach would be to increase reboiling duty and increase reflux flow. This will help in better separation, and it will also increase the pressure of the stabilizer top. Try in filed and check.