Crude Oil + Gas Flow Measurement

[lacv2k]

Dear Sirs,

Someone can help me to get the best possible solution to measure flow of crude oil (liquid) mixed with some gas? I usually use turbine and positive displacement, but they are not accuracy with gas presence.

Thank you in advance for your help,

Best regards,

LACV

 

[zdas04]

If I had an answer to that problem I would own an island in the Carabian.

Multi-phase flow is inherently unstable. All of the stuff that tries to quantify a flow rate (I won't call any of the alleged "2-Phase Meters" "measurement") starts with an assumed flow regime. The assumption is valid for dozens of mili-seconds at a time, but it is invalid much more often.

You cannot do custody-transfer-quality measurement on 2-phase flow. Looking at some of the research that has been published, I don't think that anyone is any closer to being able to do this today than I was when I wrote my Master's Thesis on this subject back in 1993.

If you are doing custody transfer then you need to do separation first.

David

 

[jmw]

One option is to persist with the positive displacement meter and use an entrained gas density meter.
The PD flowmeter measures the true volume flow but cannot tell how much of that volume is liquid and how much is air.
The entrained gas density meter can determine the density of the gas/liquid mix with good accuracy.
These two measurements will give you mass flow.
If you knwo the density of the crude, you could back calculate the volume floww of crude.
The entrained gas density meter is good for gas entrainment from 0-100%.
The next option is to look at |Coriolis flow meters.
In pursuit of multiphase flow these have been imporved to the point where they can handle two phase flows with upo a certain amount of entrained gas.
Mnaufacturers offering this include Micromotion and Invensys.
They claim excelent mass flow capability. Not sure how good the density is.
I wouldn't know waht to do with vlecoity or inferentila meter types like trubines but the PD meter solutionis pretty good.

http://www2.emersonprocess.com/en-U...y-meters/ELITE-high-capacity/Pages/index.aspx

and an email to

http://www.viscoanalyser.c

om will get you an answer back on the PD meter and EGA density solution.


JMW

http://www.ViscoAnalyser.com

 

[glowing]

coriolis.

The only way I know of is with a coriolis that has the ability to measure entrained air. Many of the newer meters have this ability.
Not sure if it will qualify as custody transfer, nor should it because if you have gas, there will likely be some water