Abstract

Oil recovery from reservoir usually leads to a reduction in reservoir pressure, reduction in recovery efficiency and thus production rate. Hence, EOR methods has been used as an efficient technique for improving oil recovery efficiency. One of the techniques is nitrogen N2 injection. For miscible or immiscible gas injection, N2 is a suitable gas to be used other than carbon dioxide. N2 is a good reservoir pressure maintenance when compared to carbon dioxide. From past studies, N2 injection was proved to be able to recover up to 45-90% of initial reserves. Therefore, the aim of this study is to determine the effect and productivity of nitrogen injection on oil production in the Cornea Field. This study was conducted because there was no investigation on the effectiveness of N2 injection to improve oil production in the Cornea Field. The model was validated by comparing MMP obtained from the result with MMP correlation methods. Correlations were used because it was more time saving and easier method despite its accuracy. From the correlation calculation, the closest MMP is 27 bar and MMP from simulation of this reservoir is at 30 bar. Therefore, the model is proved valid. Sensitivity analysis were conducted by varying different reservoir properties such as initial reservoir pressure, reservoir temperature and N2 injection rate. From the result, oil production increased with decreased in pressure and increased in temperature. On the other hand, oil production fluctuated with increased in injection rate.

Keywords:Pressure maintenance; Nitrogen injection rate; Reservoir temperature; Minimum miscibility pressure; Reservoir simulation

List of Abbreviations

Table 1: List of symbols (Abbreviations Descriptions).

Nomenclature

Table 2: Symbol descriptions and units.