Measurement of 3 Phase Flow 1

[Khansahib]

Production (Water, H/C Liquid and Gas) from a well is to be measured; a three phase metering system is one possibility but due to complications it is at low priority. The other possibility I am looking at is that the gas be separated prior to metering skid by installing a riser on the production line, as indicated in the attached sketch. The riser is then be Tied – in to the production separator outlet. In this line up the liquid will follow the normal path (through manifold) to separator and gas through riser. Further to stop the liquid carry over a liquid trap can be installed on the gas riser before gas metering. I would like to know if someone has used this option. I will appreciate your comments and suggestions.

 

[dcasto]

The mixture will take the path of least resistance, why would just the gas want to go through the riser and not the normal path.

 

[Khansahib]

decasto,
Thanks for your response, I agree to your point that it will take ther least resistance path. This question is posted to gain the knowledge about how to balance the split flow for metering purpose.
Following are the reasons which is restricting us not to flow the 3 phase through normal path. a) The cost of multiphase meter, b) accuracy, c)maintenance of the meter, d) variable the (GOR) gas to oil ratio d) the meter is highly sensitive, e) the driving source of the meter is radioactive.

 

[dcasto]

why not use simple technology. You have a seperator, measure the three outlets with simple orifice meters or ultra sonic meters.

Or how about this

http://www.documentation.emersonpro...blic_mmisami/documents/brochures/gi-00713.pdf

 

[Khansahib]

decasto,

It is being measure after separator but this measuremnt is for the entire field and not for a single well. There is a test separator as well and routinely each well is checked as well. The production would like to reconcile daily production figure with daily production from each well that is why metering on each well production line is required.

 

[MortenA]

There is no attached scetch - but from what i can read i think i saw a commercial multiphase meter the same as you suggest. Its like a small test separator with meters on each phase.

These guys has one:

http://www.ep-solutions.com/Solutio..._Systems.htm?gclid=CNehuuyd0pICFQhWMAodtGfVCA

and these

http://www.phasedynamics.com/ccm.html

But im sure its the one i once looked at so theres propably more out there.

These guys have a very differen approach that i find interesting:

http://www.multiphase.com/products/p_vmetering.htm

They take already known measurements at various points in the process and uses them to calculate flow but chosing the one that give the best result based on operating conditions.

E.g. when flowing wellhead pressure is high dP across the choke is used and when flowing wellhead pressure is low bottom hole pressure and flowing wellhead pressure is used - combined with appropriate flow models.

Best regards

Morten

 

[avirex]

I have another question please, how can I verify the volumetric flow rate reading from a flowmeter in new facility, with information on throghput (BOPD), GOR and water cut. I already used the GOR value (scf/stb) to multiply the daily thruoghput, that gives me the gas volume in SCFD. The value I obtained in SCFD i converted to flow rate in std_m3/hr, therafter I converted this to Act_m3/hr with the eqn as below;

Std_m3/hr x (Pstd/Pact) x (Tstd/Tact)

But on using for thesame model I got a totally different actual flow rate, but at standard conditions they seem similar. Can anybody please tell me how to go about such problem, 'cos from what I noticed in the HYSYS model, some of the gas has dissolved in the HC-crude, making the volume to be smaller, thereby increasing the volume of the HC crude

Can anybody in the house give me an acceptable way of calculating gas flow from a 3-phase separator, that can be used as verification for gas meter meter rading at different inlet flow rates, if you have GOR, watercut HC fluid daily production rate

Will be very happy for any contribution.......thanks

 

[JLSeagull]

http://www.agarcorp.com/flowmeters.html

Consider the Agar multi-phase flow meters. I have never bought one but keep Agar in mind if ever needed.

 

[maddocks]

You could also look at ultrasonic or even a mass coriolis meter for 3-phase metering. I'm not sure if you can get a water cut out of them, but they will provide a mass/density measurement.

 

[narj]

i have the autoclave as a batch reactor ,i want to mix oil and water at 60-80C , i want to know the temperature and pressure needed ? the temperature can be between 200-400C , can any help for the expecteed temperature profile against pressure ?

narj

 

[Khansahib]

(b)avirex (/B)(Chemical),
The way you are doing seems to be normal however, the crude will have high RVP as the gases will dissolve in crude as the pressure goes high.May be you find or draw a graph of your crude solubility from hysis simulataion at different pressures or get a lab draw you a graph based on the crude RVP and then add that value in your model

 

[avirex]

@ Khan

thanks I will get the lab, to provide info on the crude solubilty graph, 'cos i need to get to the bottom of this.......thanks