7 replies to this topic

[Pingue2008]

Dear,

 

I am working on a de-bottlenecking project on my packed column. yesterday as I was thinking of ways to improve our packed column I thought about installing few trays at the bottom of the packed column so that the separation column can handle more load. let me back-up a bit. the separation colm separates water from ethylene glycol. the plant was originally designed to handle 250TPD. Over the years managements made few changes to creep up to 460TPD . However, the separation colm was one of the things that was changed or improved upon. we are also space limited (can't get bigger diameter colm even if we wanted to).

 

Simple question: Has any of you done what I am proposing? if so how successful was it?

 

Thank you,

[PingPong]

Usually columns are debottlenecked by replacing trays by packing, not the other way around.

 

You do not tell what kind of packing the column now has, but you could consider to replace the lower part of the packing (or all the packing) by more modern packing with higher hydraulic capacity. Be careful however that you do not lose theoretical stages which would have a negative impact on the separation.

[Bobby Strain]

You should ask tray and packing providers such as Koch-Glitsch and Sultzer. You can find links to them on my website. Just Google my name to find it.

 

Bobby

Edited by Bobby Strain, 03 December 2015 - 12:22 PM.

[breizh]

Hi ,

As stated above consider new type of packing ( if possible) and contact the big guys ( like Koch and Sulzer ) . Be careful if you select the new packing to get guarantee , don't buy "looks like" , example "like BX or BX+ "

 

 

Hope this helps

 

Breizh

Edited by breizh, 05 December 2015 - 05:49 AM.

[Padmakar Katre]

Dear,

 

I am working on a de-bottlenecking project on my packed column. yesterday as I was thinking of ways to improve our packed column I thought about installing few trays at the bottom of the packed column so that the separation column can handle more load. let me back-up a bit. the separation colm separates water from ethylene glycol. the plant was originally designed to handle 250TPD. Over the years managements made few changes to creep up to 460TPD . However, the separation colm was one of the things that was changed or improved upon. we are also space limited (can't get bigger diameter colm even if we wanted to).

 

Simple question: Has any of you done what I am proposing? if so how successful was it?

 

Thank you,

 

Hi,

I presume there are hydraulic limitations in the tower since throughput has increased significantly. This limitation has indirect effect on separation efficiency. Instead of going with augmentation of trays, consider providing another bed of packing to get more number of stages. The options below are worthwhile to consider,

1. Replacement of packing with high efficiency at a marginally higher pressure drop: it's unclear what type packing is there in existing tower, if it's random then you can explore possibility of using structured packings

2. Augmenting the packing depth or another packed bed subject to availability of space/height in column. At the max you can consider increasing column height the extent the current foundation/structure permits.

 

Conventional trays will have lower Turn-up capacity than packing hence I will recommend to rule out possible use of trays. Another option is use ultra high capacity trays like Koch UltraFrac and Shell/Sulzer ConSep which works on principle of centrifugal force where multiple 'g' are possible. Conventional trays work based on Souder's & Brown gravity separation mechanism where there is only one gravitational constant and these trays have limits which in tray hydraulics terms called as 'System Limit'.

 

As suggested by forum members, you can get in touch with Sulzer/Koch Glitch like vendors which will definitely help you and propose suitable revamp solutions.

[Pingue2008]

Thank you so much for your inputs.

Just as note what i currently have random packing. I am limited by both the height and diameter.

Again thank you for your inputs.

[PingPong]

Replacing random packing by structured packing should give you a considerable increase in hydraulic capacity at the same, or even more theoretical stages.

[shantanuk100]

Hi Pingue,

 

1. Usually Revamping or Increasing Capacities for Columns is done by adding a Packed Column to an already existing Trayed/Packed Column. Trayed columns are usually not used for revamping unless you have some sort of Diameter Restrictions.

2. You also obtain more absorption efficiency and capacity for a lesser height of Packing than you do for trays, since the number of stages will be higher.

3. You will also need to check and see if Vertical Column space is available for the redistribution of liquid between the Beds.

4. If you have some sort of Height restrictions, it is better to go for Packed Column to increase the existing capacity. As the others have said, you will need to contact and talk to Sulzer or Koch-Glitsch etc., on how they can suitably cater to the specific need you have with your limitations.

 

Regards,

Shantanu