2 replies to this topic

[Poet]

Hello, I'm process engineer.
I'm looking for some solutions or appropriate judgement about my current project.

There is a gas lift system. (not gas injection)
Lift gas is compressed for transfer via gas lift line, but its temperature is continuously decreased because of heat loss by ambient.
Therefore, its phase eventually goes compressible liquid and this phenomenon is inevitable in the situation. (Plz refer to attached phase diagram)

So far, I have known that gas lift principles are the following.
1. Density difference between lift gas and oil in well. Lift gas is mixed with oil and its density is lowered.
2. Scrubbing tubing by lift gas.

My question is,
1. I would like to know such fluid at compressible liquid phase can be used to gas lift even though it's not gas phase.
For your reference, current compressible liquid density is 425 kg/m3 at gas lift inlet and oil density is about 815 kg/m3 at well head.

2. If fluid reaches gas lift inlet at supercritical phase (=dense phase), can it be used for gas lift as well?

Thanks.

Attached Files

•  phase diagram.jpg   95.93KB   1 downloads

[Bobby Strain]

If this system is in operation, look at the design documents. Use your favorite search engine for an overwhelming amount of information.

 

Bobby

[Pilesar]

I think you provided your own answer when you wrote 'Lift gas is mixed with oil and its density is lowered.' As long as the result is a density gradient with a lighter oil mixture above the injection point, then there will be a driving force to move the oil. The lowered mix density has a reduced head pressure in the wellbore. The higher pressure oil outside the well is driven into the wellbore by the resulting pressure gradient.