2 replies to this topic

[Steve90]

Hi guys ;

 

I want to know why in most natural gas treatment units before the dewpoint unit we dehydrate the gas using a TEG Unit when we can reach in some case sales gas water content specification only with the dewpoint control loop ( recuperate water in the bottom of the LTS Vessel) ?

I have a doubt about using the TEG Unit to prevent Hydrate formation but i tested a real case using hysys and the simulator indicated that there is no hydrate formation ?

 

thanks 

[serra]

GPSA (Engineering Data Book) has useful information, there could be different reasons to include TEG unit, normally based on process specs,
I can't comment the results of hysys for hydrates (I use a different software, Prode, to predict hydrate formation) but  take care about possible errors...

[RockDock]

I would not use Hysys for hydrate calculations. It is not their strength. I have only heard of Prode on this forum and have not seen that at any operating company I service. The most used software I see for this calculation is ProMax. Hysys hydrate values are not trusted by many operating companies.

 

You certainly need to dehydrate the gas before the demethanizer or deethanizer. TEG gets the job done for low ethane recovery plants, but you would need a mol sieve if you are going to recover meaningful amounts of ethane.