Design of Amine Contactor 1

[chemical13]

Hi, I am designing amine contactor for H2S removal using MDEA. I am using packed tower with IMTP packing of 1.57inch diameter and the bed diameter is of 3ft. I want to calculate the column height, I need information regarding the retention time of the liqulid in the column. Can anyone help me? Thank you.

 

[mbeychok]

chemical13:

Your posting is not very clear. Do you mean that you are trying to calculate the packed bed height by knowing the liquid retention time? If so, that is not the way to calculate the bed height. First, you need to calculate (a) the number of theoretical plates needed to get your desired H2S removal. Then you need to (b) obtain the HETP (Height Equivalent to a Theoretical Plate) from your packing vendor or elsewhere. Then multiply (a) times (b).

Or do you simply want to know the liquid retention time for the liquid in the bottom of the column beneath the packed bed?

Milton Beychok
(Visit me at www.air-dispersion.com)
.

 

[chemical13]

I just wanted to know the liquid retention time for the liquid in the bottom of the column beneath the packed bed.

 

[mbeychok]

Chemical13:

My rule-of-thumb is to use 5 minutes of retention time between the normal liquid level and the bottom of the vessel. Also, be sure to provide enough space above the normal liquid level for a high level alarm. And be sure to provide a liquid level controller on the bottoms outlet line.

Others may probably have different rules-of thumb.

Milton Beychok
(Visit me at www.air-dispersion.com)
.

 

[dcorllc]

I am trying to remove Bicine from an Amine unit. Any ideas how to do it?
Iam looking into ion exchange units. Any one with experience as to the type and conditions for best results.

Thanks

dcorllc

 

[Jason5000]

dcorlic,

Its a very generic answer, but I suggest you start out by Googling solvent reclaiming. There are a number of companies using different technologies like ion exchange, electrodialysis, and vacuum distillation.

Sometimes normal losses and makeup to a system are sufficient to keep concentrations of contaminants low. If you are experiencing a buildup of undesirable stuff in your amine, the companies that provide these solvent reclamation services should be able to provide a solution. It might not hurt to check with your amine supplyer to see what they recommend too.

Good luck,

Jason

 

[maddocks]

I try and get 5 minutes of retention time in the contactor bottoms - this will help the level controller not react so frantically. I'm a big proponent of residence time in amine systems, especially in the lean side prior to the charge pumps.