Method for enhancing the retention efficiency of treatment chemicals in subterranean formations

A method for retaining a treatment chemical in a subterranean formation containing hydrocarbons is disclosed. The method includes first preparing an emulsion. The emulsion contains an oil continuous phase and first and second aqueous phases. The first aqueous phase includes a treatment chemical, such as a scale inhibitor. The second aqueous phase comprises a retention enhancing chemical which is to be reacted with the treatment chemical in the subterranean formation. Preferably, the first and second aqueous phases remain generally separately dispersed and stable within the oil continuous phase prior to being introduced into the subterranean formation. The emulsion is then placed down a well bore and into the subterranean formation. The first and second aqueous phases then interact with one another in the subterranean formation such that the treatment chemical and the retention enhancing chemical react with one another resulting in the treatment chemical being retained in the subterranean formation at a greater efficiency than had the second aqueous phase, including the retention enhancing chemical, not been used.