7 replies to this topic

[ryn376]

I'm sorry for the basic question, but I come from the specialty chemicals world and came across a gas industry P&ID I don't understand at all (don't worry my job isn't P&ID or tower design on this...). Can somebody explain to me what is going on with this tower? Sorry for the hand sketch, but I cannot attach the actual P&ID. Thanks for your help.

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[breizh]

hi ,

Consider the resource attached to support your work.

Good luck

Breizh

[gegio1960]

ryn376,

you have 2 stacked vessels:

- the (rich) amine regeneraror (column) above

- the column overhead accumulator below....integrated with the column heater(?)

the design seems compact but not very efficient.

for sure, this design is not adopted in refineries/gas plants (my fields), where amine regenarators are (almost) mandatory pieces of equipment.

maybe, you've other specific questions...

good luck!

[Sharma Varun]

 

you have 2 stacked vessels:

- the (rich) amine regeneraror (column) above

- the column overhead accumulator below....integrated with the column heater(?)

 

However for lean amine there should be only one stream i.e. regenerator column bottom, lean amine indicated as entering from top must be reflux 

[ryn376]

I tried to show stream elevations exactly as shown on the P&ID. Thank you for your responses. A few more questions.

-Are the rich amine and lean amine both liquids?

-What is the lean amine stream for?

-What is going out the top of the tower to the condenser?  I assume that the point of this is to remove H2S and CO2 from the rich amine out the top of the column.

-Are there trays in the bottom or is the heating water added directly to the distillate (is that even the right term for this)? Does the distillate take CO2 and H2S with it or just the small amount of water vapor that flashes from one of the amine streams?

Edited by ryn376, 11 March 2020 - 09:53 AM.

[gegio1960]

@sharma: agree. and there should be a pump somewhere.

@ryn:

1) Are the rich amine and lean amine both liquids? ---yes

2) What is the lean amine stream for? ---it is used somewhere for washing/sweetening acid gases

3) What is going out the top of the tower to the condenser?  I assume that the point of this is to remove H2S and CO2 from the rich amine out the top of the column. ---yes. at the top you have sour gases

4) Are there trays in the bottom or is the heating water added directly to the distillate (is that even the right term for this)? ---stripped/sour gas is a better word. about the presence of trays, probably no...but the plant is yours.

5) Does the distillate take CO2 and H2S with it or just the small amount of water vapor that flashes from one of the amine streams? ---CO2/H2S and water in the stripped gas

[Nikolay_]

Hello,

The regenerator is like one I saw in article "Improved Absorber-Stripper Technology for Gas Sweeting to Ultra-Low H2S Concentrations" by G.P. Towler, H.K. Shethna, B.Cole, B. Hajdik.

Edited by Nikolai T, 16 March 2020 - 09:15 AM.

[Technical Bard]

Stacking the KO drum after an amine column used to be quite common to make plants have a smaller footprint and reduce the number of foundations needed.  But it isn't commonly done today, often because modern design recognizes that the internal head can be a stress problem area.  In this case, I suspect the "heating water" he has listed is actually a coil inside the KO drum to COOL the gas (the water is being heated) further, knocking out water/amine.