| abstract |
Clean-up additive compositions may be used to enhance the clean-up of VES-gelled aqueous fluids in a wide range .of .applications and VES fluid compositions, including use of an internal, breaker system. The compositions are microemulsions that may include, but npt necessarily be limited to, at least , one viscosity reducing agent, at least one solubiliidng agent, at least one desorptiÌn agent and at least one water wetting agent. One non-limiting embodiment of a specific microemulsion includes an unsaturated fatty acid oil, a glycol, a sorbitan ester/ethoxylated sorbitan ester mixture, and an alkyl sulfonate. Microemulsions may perform one or more of the following functions: keeping the reservoir water wet; keeping surface tension reduction low; demulsifying reservoir crude oils and aqueous VES fluids; dispersing and solubilizing the by-products generated when breaking the VES gel; and/or limiting the amount of VES residue on reservoir minerals. |