doctoralThesis
Avaliação de sistemas constituídos por polímeros/ tensoativo/ EDTA na recuperação avançada de petróleo
Fecha
2015-10-19Registro en:
SANTOS, Joselisse Soares de Carvalho. Avaliação de sistemas constituídos por polímeros/ tensoativo/ EDTA na recuperação avançada de petróleo. 2015. 97f. Tese (Doutorado em Engenharia Química) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2015.
Autor
Santos, Joselisse Soares de Carvalho
Resumen
Enhanced oil recovery has been the focus of countless research projects
aiming for the improvement of the in place oil recovery from the reservoirs, especially
because mature fields and/or fields containing heavy oil require further assistance to
ensure oil flow and consequent production. Having that in mind, physical and chemical
properties such as the rheological behaviour and the superficial tension of polymers, for
different concentrations and temperatures, were studied. After obtaining the polymers
critical aggregation concentration (c.a.c.), the interfacial tension (IFT) between the
polyacrylamide/oil solutions was evaluated, as well as for the solutions containing
surfactant (SB) and EDTA. The permeability and the application of those solutions in
enhanced oil recovery of those solutions was also observed using the Botucatu arenite.
The results obtained demonstrated that the increase in the polymers ionicity promotes an
increase in the solution viscosity. An increase in temperature reduced the viscosity for the
low ionicity polyacrylamides, but caused an increase in the viscosity for some of the high
ionicity ones. Concerning permeability, the anionic polymers presented higher injection
pressure values when compared to the lower ionicity ones, and that behaviour is believed
to be related to the viscosities of those polymers, which are higher. Regarding superficial
tension, the c.a.c. region for each polymer was observed, and the conclusion was that the
ionic charges had little or no influence in the reduction of interfacial tensions between the
oil and the polymers, while the decrease in IFT for all solutions was observed when
compared to the system formed by water and oil. The aforementioned results are a good
indicator that the polymers studied are suitable for the enhanced oil recovery process. By
injecting the solutions into the porous media, it was observed that the solutions formed by
SB associated to EDTA improved the flow inside the porous media. The results indicated
that the enhanced oil recovery using the polymer/ surfactant/ EDTA solutions reached a
recovery factor of 18 % of the original oil. In addition, it could be observed that polymers
presenting the higher ionicity, associated to surfactant and EDTA, promoted a synergy in
the enhanced oil recovery when compared to the solutions containing only polymers.