Amine Unit Reboiler

[ChihebG]

Experts,

What is the role of the Reboiler in the Amine Unit?
I am sorry if this question may be too evident to answer, I have search a lot but I didn't the appropriate answer.

Regards,

 

[EmmanuelTop]

Purpose of the reboiler is to:

- Supply energy required for heating the amine solution from the tower inlet temperature to the tower bottoms temperature;
- Supply energy required for breaking chemical bonds between amine and acid gas components;
- Supply energy required for evaporating the required amount of overhead reflux.



Dejan IVANOVIC
Process Engineer, MSChE

 

[ChihebG]

Thank you Dejan, In general what are the main inputs and outputs of the reboiler?

 

[EmmanuelTop]

What do you mean by inputs/outputs? Fluids? Mechanical connections? Control variables?

Dejan IVANOVIC
Process Engineer, MSChE

 

[ChihebG]

I mean what are the fluids treated within the Reboiler.

 

[EmmanuelTop]

Lean Amine solution is circulated through the reboiler (usually via thermosyphon loop) by the heat supplied on the tube side of the reboiler. Water from amine solution partially evaporates and becomes steam, which supplies the required heat for the 3 processes listed above. So there is amine solution on the shell-side of the reboiler, and a heating fluid on the tube-side of the reboiler.

There are quite a few sources of information on Amine units on the web. See for example:

http://refiningonline.com/abpg_kb/ABPG-5.pdf

http://www.energy.alberta.ca/CCS/BDEPAmineUnitAppendix.pdf

Dejan IVANOVIC
Process Engineer, MSChE

 

[ChihebG]

Thank you Dejan

 

[georgeverghese]

The reboiler is operated as a kettle reboiler, with lean amine overflowing a weir in the heating bundle section.
Level downstream of the weir (which is at the same level as the bottom lean amine sump of the stripper) should also take up the thermal expansion volume of the entire amine solution closed loop inventory going up from cold temp conditions to normal operating temp.
Maintenance volume holdup for the circuit is usually provided in a separate rich amine storage tank. This is unlike a TEG unit, where the maintenance volume holdup is provided in the lean TEG surge drum - in an amine unit, there is no surge drum