doctoralThesis
Estudo da configuração de poços no processo de drenagem gravitacional assistida por vapor (SAGD) em reservatórios do nordeste brasileiro
Fecha
2016-09-02Registro en:
FERNANDES, Glydianne Mara Diógenes. Estudo da configuração de poços no processo de drenagem gravitacional assistida por vapor (SAGD) em reservatórios do nordeste brasileiro. 2016. 151f. Tese (Doutorado em Ciência e Engenharia de Petróleo) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2016.
Autor
Fernandes, Glydianne Mara Diógenes
Resumen
New technologies that use the enhanced oil recovery emerged the need to remove the
oil that remains in the reservoir after primary recovery. The goal of these methods is to
increase the oil recovery factor. Thus, some projects start to become economically viable
when using these methods. The thermal methods, including steam injection, promote the
recovery of oil through the thermal energy within the insert reservoir. The increased
temperature causes the oil to have its viscosity reduced, thereby increasing its speed towards
the production wells. The steam assisted gravity drainage process (SAGD) is an advanced
method of recovery. Its configuration has two parallel horizontal wells, one above the other.
The steam is injected continuously during the injection well, and then forms a steam chamber
which grows to find the limits of the reservoir. This oil is then reduced its viscosity and, by
the action of gravitational forces, it is drained toward the producing well. In this context, this
study aimed to carry out a study of different configurations of injection wells in SAGD
process, considering the effects of load loss and heat in the injection well in the Brazilian
northeast reservoirs. A factorial design was used to investigate the influence of the parameters
studied in the recovery factor. It also performed an economic analysis of the technical settings
of injection wells in order to analyze the profitability of the projects studied. To perform the
numerical simulations we used the thermal simulator CMG STARS (Computer Modelling
Group). The results showed that the inclined injection wells had a lower production compared
to the configuration with horizontal wells. A setting producer injectors offset from the well
(W-SAGD) for injection flowrates from 100 ton/day, led to the formation of a vapor chamber
larger and more efficient. It was also observed that the use of vertical injection wells (VSAGD),
for larger flowrates, showed a lower cumulative production of oil, however, similar to SAGD injector well horizontally. In the economic analysis, the SAGD model showed the
highest NPVs.