Simulation Study of Re-Entry Drilling for Gas/Condensate Reservoir Development

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractGas-condensate reservoirs usually exhibit complex flow behavior due to the near-wellbore condensate bank build-up when bottomhole pressure drops below the dew point. Such an accumulation of condensate liquid in the near-wellbore region forms a ring that may significantly reduce the gas relative permeability and consequently the well productivity. Also, when reservoir pressure drops below the dew point, a big portion of condensate liquid will remain in the reservoir and will not be produced.Many condensate reservoirs have been producing with vertical wells. This paper presents a practical strategy of rejuvenating gas-condensate reservoir production through multilateral sidetrack reentry drilling technology. Simulation studies show that reentry drilling through vertical wells can help break the condensate bank damage and significantly increase well productivity.Sensitivity analysis of fluid type, reservoir permeability, lateral length, and reentry drilling time on production performance, is conducted. Results show that multilateral reentry drilling represents a very promising technology for developing medium/low permeability gas-condensate reservoirs.