The gas-oil interfacial behavior during gas injection into an asphaltenic oil reservoir

Escrochi, M ; Sharif University of Technology | 2013

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  1. Type of Document: Article
  2. DOI: 10.1021/je400403y
  3. Publisher: 2013
  4. Abstract:
  5. Oil displacement and recovery efficiency during gas injection depends on the competition between driving forces and capillary resistance that is governed by gas-oil interfacial behavior. Detailed study of the interfacial forces during gas injection is the main objective of this research work. The effects of injecting gas composition and the possibility of asphaltene precipitation in a wide pressure range were determined through comprehensive experimental study. This was performed by measurement of interfacial tension of a highly asphaltenic Iranian crude oil in three surrounding gas mediums. The results showed that as pressure increases, the rate to reach miscibility reduces in the vicinity of the asphaltene precipitation onset. As the surface coverage of the asphaltene at the gas-oil interface exceeded a threshold value the rate was reduced furthermore. Component extractions, noncondensable gas film formation, asphaltene precipitation, and asphaltene accumulation at the interface are found to be the main parameters affecting the miscibility. The observations showed that miscible displacement is practically impossible for this asphaltenic crude oil. Dimensional analysis proved that pressure increase in N2 and flue gas injection is not effective in improving oil recovery; however, CO 2 tests revealed the presence of optimum pressure range with highest gravity drainage potential and minimum capillary resistance
  6. Keywords:
  7. Asphaltene precipitation ; Component extraction ; Dimensional analysis ; Interfacial behaviors ; Interfacial forces ; Miscible displacement ; Non-condensable gas ; Recovery efficiency ; Asphaltenes ; Carbon dioxide ; Crude oil ; Gases ; Petroleum reservoirs ; Solubility ; Phase interfaces
  8. Source: Journal of Chemical and Engineering Data ; Volume 58, Issue 9 , 2013 , Pages 2513-2526 ; 00219568 (ISSN)
  9. URL: http://pubs.acs.org/doi/abs/10.1021/je400403y