masterThesis
Adição de polímero em microemulsão: caracterização e efeito do seu uso no teste Eor
Fecha
2019-07-29Registro en:
FELICIANO, Nathália Oliveira. Adição de polímero em microemulsão: caracterização e efeito do seu uso no teste Eor. 2019. 82f. Dissertação (Mestrado em Química) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2019.
Autor
Feliciano, Nathália Oliveira
Resumen
After exhaustion of its natural energy, the reservoirs retain high amounts of hydrocarbons.
The use of conventional methods is associated with pressure maintenance operations, which
leads to a displacement of about 30% of the oil and this is due to the high oil viscosity and the
elevated interfacial tensions between the injection fluid and the fluid to be displaced. The
application of improved oil recovery methods, therefore, is given as a way to increase the oil
recovery factor resulting from the use of conventional recovery, since this method is based on
the reduction of viscous and capillary forces. Among the improved recovery methods, there
are thermal, miscible and chemical methods. The application of the chemical methods is done
when a certain chemical interaction between the injection fluids and the fluid to be displaced
is desired. This work aims to study microemulsion systems (with and without polymer in its
composition) for the improved recovery of oil, determining the phenomena of interface and
viscosity, and evaluating their recovery efficiencies. For this, these systems were
characterized by measurements of aggregate size, viscosity, surface tension, contact angle and
oil recovery. The microemulsion systems were obtained by choosing points in the
Pseudoternary diagram, of the following composition: Ultranex Np 120 (Surfactant - T),
secondary butanol (Co-surfactant - C), heptane (oil phase - FO), distilled water (aqueous
phase - FA) and polyacrylic acid (polymer), in a fixed ratio of C/T = 1. The chosen systems
have a fixed quantity of 5% m/m FO, while the quantities of C/T and FA vary between 35 and
60%. The systems with polymer in its formulation were obtained with the addition of 0.2%
m/m of the polymer. The IOR tests were carried out using plugs from sandstone rock from the
Botucatu formation and the oil from the Ubarana field in Rio Grande do Norte. A comparison
made between the surface tension results and the viscosity measurements showed that the oil
displacement, for the systems without polymer, is mainly due to interfacial action, while for
the systems with polymer, the recovery obtained is mainly due to mechanical displacement. In
addition, all the systems under study presented positive results for improved recovery,
increasing the wettability of sandstone, reaching 41% of original oil in place recovery (%
OOIP).