METHOD TO DETERMINE MASS FLOW RATE OF GAS-AND-LIQUID MIXTURE Russian patent published in 2008 - IPC E21B47/10 G01F1/86 

FIELD: oil and gas production geophysics, particularly to determine mass flow rate of oil, gas and water in multiphase flow passing from well via pipeline.

SUBSTANCE: method involves simultaneously measuring gas content of multiphase flow with the use of gas meter and oil-and-water content with the use of multiphase flow meter, which calculates oil-and-water phase volume and mass. Said calculation is carried out by variable pressure-drop method, which uses differential pressure in restricted multiphase flow meter section. Pressure difference in said restricted section provides the measuring of oil-and-water emulsion flow rate, which is connected by following relationship: greater flow-rate of fluid passing through multiphase flow meter increases pressure difference. Knowing differential pressure flow density is determined from well-known mathematical expressions as quotient of differential pressure by squared flow velocity. Then using obtained flow density values volume and mass of oil-and-gas phase in flow passing via multiphase flow meter may be calculated. Summary oil, gas and water flow-rate in multiphase flow is determined on the base of measurements in gas meter and multiphase flow meter. After that the obtained results are corrected on the base of correction factors, which take into consideration mixture composition and ratio between oil and water fractions. Said correction is carried out in accordance with capacity and conductance measurements in multiphase flow meter channel.

EFFECT: increased accuracy of gas-and-liquid mixture flow rate determination, possibility to protect staff against radioactive radiation.

3 cl, 1 dwg