Abstract
Nitrogen injection is a proven technology for Improved and Enhanced Oil Recovery. This paper explains the recovery mechanisms and infrastructure requirements, and highlights its advantages as a low cost and water saving process for the arid North African region. A case study from Cantarell/Mexico demonstrates its applicability. The assessment of oil fields in Algeria, Egypt, Libya and Tunisia shows the potential of the technology for the North African region.
Nitrogen injection can be used for gas cap pressure maintenance, immiscible or miscible drive of oil fields. The technologies for nitrogen production by air separation and for nitrogen rejection from associated gas are explained. A case study of nitrogen injection is shown. The capital expenditure and consumption figures are given. A screening method for North African oil fields is explained, including the oil and reservoir screening criteria, as well as ratios for nitrogen demand and incremental oil production.
Nitrogen is produced from air, and therefore universally available as an inert and low cost injection fluid. The technology can be used in onshore and offshore environments, and especially in areas where water is scarce. The case study of nitrogen injection in the Cantarell oil field in Mexico shows the positive production result of nitrogen injection. The assessment of North African oil fields shows a very good potential for the application of the Technology. A total of 48 oil fields in Algeria, 49 fields in Egypt, 50 fields in Libya and 19 fields in Tunisia have been identified with good potential for nitrogen injection with up to 10% incremental recovery factor of the Original Oil In Place.
The paper summarises the foundations of nitrogen injection for Improved and Enhanced Oil Recovery, especially with a focus on the surface related technology installations for the North African region. The oil field assessment including injection result estimate and nitrogen capacity requirements is new for the region and in the literature.
