Hydrate Formation 1

[luffe]

I am interested to find out whether glycol or methanol is more effective in dissolving hydrocarbon hydrates. It is my understanding that methanol is the more effective, but would like to hear some expert views.

Thanks,

S. Whitehead.

 

[TD2K]

My understanding is similar to yours. While glycol is effective at preventing hydrates, it's not very effective in melting them. Methanol is typically used for this purpose.

 

[whoislee]

Methanol has a higher solubility for water (the source of hydrates) compared to glycol.

However as methanol has a low boiling point, it is not used in gas dehydration facility. Glycol is normally used here.

Methanol is used more for temporary retardation of hydrate formation in pipelines, before sending the natural gas for further processing by downstream equipments.

Methanol is costly compared to glycol.

What application do you need these chemicals for?

There are 2 sides of a coin
One is to give, one is to take
Give until it hurts with a smile

 

[luffe]

Thanks for the reply whoislee.

The application is during new well clean up to a flare and potential well intervention work in wells which may have some residual water based drilling fluids in them.

I am keen to resolve the question of which chemical is more effective in 1. dissolving hydrates which may be present in the wellbore and 2. inhibiting the formation of hydrates in the temporary flowlines, bearing in mind that the quantity of associated water is unknown and is only a temporary situation (hopefully). The wells are normally free of water after a period of time. Recovery and cost are not an issue.

 

[whoislee]

For the well, would recommend methanol. Methanol will be able to dissolve under high pressure compared to glycol.

Since cost is not a factor, no issue with methanol.

Hope this helps.

There are 2 sides of a coin
One is to give, one is to take
Give until it hurts with a smile

 

[SuperTy]

Methanol is more effective, but it is also flammable. Some operators have reservations about this, wheather practical or not. Methanol pumps should be readily available through most service companies in just about every operating area.