Offshore TEG Gas Dehydration - Water in ppm Achieved

[DoraeS]

Hi, I would like to know what is the lowest water dew point (in ppm) that can be achieved using typical TEG gas dehydration design for offshore, without going into those proprietory licensing design (e.g. Coldfinger)? Is 1ppm the lowest?
And what is the lowest whe stripping gas (e.g. fuel gas) is used?

Many Thanks.

 

[atayto]

Generally gas water content depends on many process variables. the major one is contact temperature(in many cases -gas temperature and also corresponding glycol concentration. Stripping gas is required for increasing glycol concentration. But still gas temperature is major contributing factor. Another factor is contactor theoretical stages.in My experience i havent seen any gas water content lower than 15ppm(w). and without stripping gas 30ppm(w). But this was with high glycol concentration and low gas flow through the contactor.I would suggest to contact contactor internals companies. they can suggest lowest water content for your particular case. for example Sulzer or Koch-Glitch.

 

[MortenA]

If you need to go really low additional tecknologies to TEG may be required e.g. adsorption.

Best regards

Morten

 

[dcasto]

Nowhere near enough information coldfinger is not proprietary anymore. A stall column is also a good choice

 

[limko]

Hi all,
the adsorption methods are very effectively in water removal but costs much than glycols such as Mol-sieve etc
but have disadvantages like high initial cost, batch process, not regenerative

 

[RRE]

For typical glycol dehydration processes (without enhancements: stripping gas, lean oil (Drizo), etc)you would do well to get water levels at ~3-5 lbs/MMscf. You could probably lower that water level with stripping gas, perhaps down to 2 lbs/MM. If you went with glycol with enhanced features like Drizo (with a stripping solvent), you will get very low water content that may apporach dewpoints near adsorption (mol sieve) processes.