石油および環境バイオテクノロジージャーナル

概要

All Aqueous Nano-Emulsion for Acid Stimulation of Oil and Gas Reservoirs

Humberto Oliveiraa, Claudio Pintob, Antonio Peres

Fluids consisting of two immiscible aqueous phases are called Aqueous Biphasic Systems (ABSs). ABSs can form Water in Water (W/W) emulsions when an "emulsifier" is added to the mixture; they are gradually becoming more prominent due to lower prices and better alignment with environmental policies compared to Oil in Water (O/W) or Water in Oil (W/O) emulsions. Still, the understanding of suitable "emulsifiers" for W/W emulsions is still in the early stages and it is usually a challenge related to very low interfacial tensions and thick water-water interfaces. This paper presents a new case of successfully stabilized W/W emulsion originated from an ABS system using a completely new chemical package concept as the “emulsifier”. This innovative W/W emulsion, that also happened to be a nano emulsion, was created with the objective of being a greener type of emulsified acid system, containing no hydrocarbons in its formulation, capable of deeply stimulating oil and gas reservoirs. Ultimately this is a new acid system, belonging to a peculiar class of fluids, being introduced to oil and gas exploration industry for the first time with the potential to be diversified and used in many interesting new applications.