Study of the effect of formation water during reserves estimation and designing hydrocarbon recovery of oil and gas condensate fields

Abstract

Currently, exploratory thermodynamic studies of the PVT reservoir fluids properties to assess the effect of condensate water on reserves estimation, design and development of the fields are carried out on Russian National and international oil companies. Such PVT ratios settings allow a wide range of pressures and temperatures to be used to study phase transitions of hydrocarbon systems. Conducted experimental studies of gas condensate systems showed a negative effect of formation water on the amount of condensate extraction during development. The studies were conducted on recombined samples of gas separation, formation water and saturated condensate taken from the wells during the pilot development of the Srednetyungskoe field in Western Yakutia. Wherein, a pattern was found of increasing the loss of high molecular hydrocarbons at the stage of the onset of condensation with increasing water vapor content in the gas condensate system. As a result of studies of the dependence of hydrocarbon losses during the increasing in the water vapor content in the system, certain parameters are the initial ones when calculating the reserves of hydrocarbon and non-hydrocarbon components in natural gas, the development of designing and field development. The aim of thermodynamic investigations was to determine the effect of formation and condensation water vapors on the condensate recovery rate during the isothermal condensation process, which manifests itself when the pressure decreases in the oil and gas condensate field.