Microemulsions, mesophase surfactant and micellar solutions, and in situ-formed fluids formulated with high density brine

摘要

Mesophase surfactant solutions and/or micellar solutions, pre-formed single phase microemulsions (SPMEs), and in situ-formed fluids may be used to clean up and remove hydrocarbons and synthetic oils such as oil-based mud filter cake and near wellbore damage in oil and gas wells. Removal occurs by solubilization of the hydrocarbons and synthetic oils into the micellar solutions, SPME, in situ-formed fluids, etc. when the fluid formulation contacts the hydrocarbons and synthetic oils. An in situ-formed fluid (e.g. microemulsion), may be formed when one or more surfactant, an optional linker, optional co-surfactant, optional acid, optional co-solvent and a polar high-density brine phase, and eventually some amount of organic phase, contacts the subterranean location and solubilizes the hydrocarbons and synthetic oils encountered, such as in the near wellbore of a subterranean formation. The micellar solutions, microemulsions, in situ-formed fluids, etc. are effective for removing the formation damage caused by hydrocarbons and synthetic oils.