Patent ID: 7653489

Claim:
A method of measuring a dry gas flow from hydrocarbon wells, said hydrocarbon wells producing liquids and natural gas so that a stream is produced, the method comprising the steps of: (a) providing a differential flow measurement device (orifice), said differential flow measurement device (orifice) having an elliptical throat, wherein said differential flow measurement device (orifice) is located at a well site containing the hydrocarbon wells; (b) testing the stream for gas composition and physical characteristics; (c) measuring a flowing temperature of the hydrocarbon stream; (d) measuring a flowing pressure; (e) measuring a pressure differential in said differential flow measurement device (orifice); (f) computing the liquid-gas ratio (LGR) of the stream; (g) computing the wet gas flow rate of the stream; (h) computing a first dry gas flow rate (Qd 1 ) utilizing a first model means, the first model means includes the following computation: wet flow rate/dry flow rate=Qwet/Qdry=(term 1 )×(term 2 )×(term 3 )+(term 4 )+(term 5 ); (i) computing a second dry gas flow rate (Qd 2 ) utilizing a graphical representation of a second model means; and (j) correcting the first dry gas flow rate (Qd 1 ) and the second dry gas flow rate (Qd 2 ) to obtain the dry gas flow rate (Qd): wherein step (j) includes subtracting Qd 1 from Qd 2 to obtain a first delta factor and comparing the delta factor to an acceptable limit, said acceptable limit being between 0.3% and 1.5% full scale (FS) of a flow measurement instrument depending on the measurement requirements; and wherein steps (a) through (j) are performed before said hydrocarbon stream undergoes a separation to separate said liquids from said produced gas in said stream.