Vent the casing gas through a venturi to lower the flowing tubing well head pressure. Note well the need for efficient flow and separation capacity downstream of the well(s). This will help during the period of sufficient differential surface tubing and casing pressures in a well with open tubing end and open annulus. The system can be cycled for intermittent flow periods and if well design permits, the well can be kicked off with the addition of high pressure gas at the casing valve. Does sand production become a problem in your field? Cyclic operations could induce sand failure.
Metering accuracy always requires single phase flow at the meter, implying separation or a phase change before metering.
Hope this helps - Jack
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Sloan Black
Oil & Gas Consultant
DentonTX
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