Abstract:

Aiming at such production difficulties as deeply buried gas reservoirs，developed fractures，containing CO₂，quick waterproducing in gas production and the production pipe string corrosion in Xujiahe reservoirs，west Sichuan，based on the factors that flow ability of formation fluid increase as the pressure difference increases，pipe string corrosion gets more severe as CO₂ fractional pressure goes up，it is presented that in gas production，the critical productivity(maximum production pressure difference)can be used in proration to prolong the period of gas production without water，the down hole throttle technique used to decrease CO₂ fractional pressure in gas production pipe string and the rate of the corrosion.The combination of the two ways can make both the proration reasonable，prolong the period of gas production without water，and ensure the control of production pressure difference,as well as decrease CO₂ fractional pressure in well bore,the production efficiency will be increased.

Key words: deep well, gas production, fixed bottom hole pressure difference, throttle, waterless gas recovery period, Sichuan Basin