FMC Technologies SONARtrac™ GVF-100 Surveillance Technology is a breakthrough technology that provides online continuous measurement of entrained gas in crude oil (gas void fraction). Its clamp-on modular architecture and patented array processing provides on-site measurement of the amount of entrained gas in oil production streams. By directly measuring secondary-phase gas, SONARtrac GVF-100 can eliminate measurement errors commonly encountered when conventional flowmeters, e.g. turbine and Coriolis meters, are used in multiphase flows.

While liquid crude oil custody transfer installations are designed to minimize the influence of secondary phase gas on measurement accuracy, even small amounts of free gas may damage the fiscal meter or cause over reporting of the liquid volume transacted. Deploying SONARtrac GVF-100 optimizes operations by eliminating entrained gas or by providing the means to correct for its influence thus restoring accurate,quality measurement and fiscal confidence.

SONARtrac GVF-100 also enables accurate measurement of separator outlet flows in the presence of gas carry-under to monitor the effects of process changes and improve separator performance.

Deployed on the separator liquid leg, SONARtrac GVF-100 accurately measures gas void fraction by utilizing an array of sensors to determine the speed of sound in the fluid mixture. The gas void fraction measurement is then used to correct the output of the primary flow measurement device to deliver accurate liquid flow rate and density information.

Applications:

• Turbine meter GVF correction
• Coriolis meter GVF density and volumetric flow correction
• Test separator outlet measurement
• Production separator optimization
• Fiscal meter augmentation/protection
• Net oil and water cut GVF correction

Benefits:

• Improved accuracy of field allocation factors
• Improved reservoir models 
• Improved separator efficiency
• Increased production
• Improved production processing