Laboratory of Microhydrodynamics and Flow in Porous Media

Emulsion formation and stability

Conjoint water and oil flow during petroleum production operations in oil reservoirs is frequently accompanied by emulsion co-production at the surface, affecting well productivity, artificial lift and separation process, depending on emulsion’s morphology. Flow conditions responsible for generation of emulsions present at the surface are uncertain.  The work being developed in our group focus on emulsion formation inside the porous space of a reservoir as well as in the two-phase turbulent flow through pipes and valves.  The goal is to visualize the break-up mechanisms, determine the critical conditions for emulsion formation and the characteristics of the emulsion formed in each situation.

The formation of emulsions in the flow through pipes, valves and pumps is studied by characterizing the emulsion morphology at different points of the flow and by visualizing with high speed imaging the flow of oil drops dispersed in water through constrictions.

The work is now being extended to study stabilization of oil-water interfaces by nanoparticles and the formation and stability of Pickering emulsions.

Recent and current research projects:

Emulsion Formation in Turbulent High shear Flows

High speed visualization of drop breakup in the flow through an orifice.
Comparison of model and experimental data on the maximum stable drop diameter in the flow through an orifice.

Recent Publications

  1. M. Gallassi, G. F. N. Gonçalves, P. N. Azevedo, T. C. Botti, J. N. E. Carneiro, M. J. Moura e M. S. Carvalho, “Experimental characterization and numerical investigation of droplet breakage in turbulent flows through orifice tubes”, submetido para publicação no Chemical Engineering Science, 2020.
  2. M. Gallassi, G. F. N. Gonçalves, T. C. Botti, M. J. B. Moura, J. N. E. Carneiro e M. S. Carvalho, “Numerical and experimental evaluation of droplet breakage of O/W emulsions in rotor-stator mixers”, Chemical Engineering Science, vol. 204, pp.270-286, 2019.

Stability of Pickering Emulsions

Deformation of Pickering drops in an electric field.
Confocal Raman microscopy of a single oil drop in (a) Laponite dispersion in DI water and (b) in a 0.1 M NaCl solution.

Recent Publications

  1. Mikkelsen, P. Dommersnes, Z. Rosynek,  A. Gholamipour-Shirazi , M. S. Carvalho and J. O. Fossum, “Mechanics of Pickering Drops Probed by Electric Field–Induced Stress”, Materials, vol.10, 436, 2017.
  2. A. Gholamipour-Shirazi, M.S. Carvalho, M.F.G. Huila, K. Araki, P. Dommersnes and J. O. Fossum, “Transition from glass- to gel-like states in clay at a liquid interface”, Scientific Reports, vol.6, 37239, 2016.
  3. A. Gholamipour-Shirazi, M.S. Carvalho e J. O. Fossum, “Controlled microfluidic emulsification of oil in a clay nanofluid: Role of salt for Pickering stabilization”, European Physical Journal Special Topics, vol. 225, 757–765, 2016