Simulation of nitrogen injection as an Enhanced Recovery Method in a tight natural fracture sandstone reservoir with compositional fluids

The construction of a dual porosity/dual permeability reservoir simulation model requires the estimation of the fracture apertures in every grid cell; generally these apertures are generated stochastically in geo-statistical models which generate a limitation in the consistency between the effective fracture permeabilities and fracture porosities measurements and interpretations. This study proposes an effective workflow to overcome the constant aperture assumption generally taken which allows adjusting the apparent aperture for each grid cell by using the matrix permeability, the critically stressed fracture intensity interpretations and the fracture permeability estimated from pressure transient analysis which results in a reliable estimation of shape factors required to estimate the fluid transfer between the matrix and the fracture. Then, using the dual porosity/ dual permeability model it was modeled the nitrogen injection in a gas condensate field. The results shows that: 1) using the Knudsen criteria and capillary pressure measurements it was found that the matrix has a conventional flow even if the permeabilities are very low, 2) the dual porosity/dual permeability model shows a higher oil and gas segregation to the bottom and to the top respectively than the conventional single porosity model due to the high fracture permeabilities, finally 3) it was found that the nitrogen injection shows significant incremental hydrocarbon gas volumes which displacement front can be optimized by adding CO2 into the injection stream.

• Autores: Herrera Guevara, Carlos Germán
• Fecha de publicación: 2016
• Institución: Universidad Nacional de Colombia
• Repositorio: Universidad Nacional de Colombia
• Idioma: spa
• OAI Identifier: oai:repositorio.unal.edu.co:unal/57083
• Acceso en línea: https://repositorio.unal.edu.co/handle/unal/57083; http://bdigital.unal.edu.co/53175/
• Palabra clave: 62 Ingeniería y operaciones afines / Engineering; 66 Ingeniería química y Tecnologías relacionadas/ Chemical engineering; Gas - Obtención y producción; Inyección de agua en campos petrolíferos; Campos petrolíferos - Métodos de producción; Fluidos composicionales; Campos petrolíferos - Métodos de producción; Pozos petroleros - Fracturamiento hidráulico; Gas manufacture and Works; Oil field flooding; Compositional fluids; Oil fields - Production methods; Oil wells - Hydraulic fracturing
• Rights: openAccess
• License: Atribución-NoComercial 4.0 Internacional