Foam-facilitated oil displacement in porous media

UoM administered thesis: Phd

  • Authors:
  • Kofi Osei-Bonsu

Abstract

Foam flow in porous media is important for many industrial operations such as enhanced oil recovery, remediation of contaminated aquifers and CO2 sequestration. The application of foam in these processes is due to its unique ability to reduce gas mobility and to divert gas to low permeability zones in porous media which otherwise would not be reached. To achieve optimum success with foam as a displacing fluid in oil recovery and remediation operations, it is essential to understand how different parameters influence foam flow in porous media. In this thesis, a variety of experimental techniques were used to study foam stability, foam rheology as well as the dynamics and patterns of oil displacement by foam under different boundary conditions such as surfactant formulation, oil type, foam quality (gas fraction) and porous media geometry. Bulk scale studies showed that foam stability was surfactant and oil dependant such that decreasing oil carbon number and viscosity decreased the stability of foam. However, no meaningful correlation was found between foam stability at bulk scale and the efficiency of oil displacement in porous media for the various surfactants studied in this work. Additionally, our results show that foams consisting of smaller bubbles do not necessarily correspond to higher apparent viscosity as the foam quality is also crucial. For the same foam quality decreasing bubble size resulted in higher apparent viscosity. Although in theory a higher apparent viscosity (i.e. higher foam quality) would be ideal for displacement purposes, increasing foam quality resulted in less stable foam in porous media due to formation of thin films which were less stable in the presence of oil. The effect of pore geometry on foam generation and oil displacement has also been investigated. Our findings provide new insights about the physics and complex dynamics of foam flow in porous media.

Details

Original languageEnglish
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Supervisors/Advisors
Award date1 Aug 2017