Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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The Analysis for the Effect of Effective Compressibility on Oil Recovery in Polymer Flooded Heterogeneous Reservoir

폴리머 공법 적용 불균질 저류층에서의 유효 압축률이 오일생산에 미치는 영향 분석

  • Baek, Soohyun (Department of Natural Resources and Environment Engineering, Hanyang University) ;
  • Jung, Woodong (Department of Natural Resources and Environment Engineering, Hanyang University) ;
  • Sung, Wonmo (Department of Natural Resources and Environment Engineering, Hanyang University) ;
  • Seo, Junwoo (Department of Natural Resources and Environment Engineering, Hanyang University)
  • 백수현 (한양대학교 자원환경공학과) ;
  • 정우동 (한양대학교 자원환경공학과) ;
  • 성원모 (한양대학교 자원환경공학과) ;
  • 서준우 (한양대학교 자원환경공학과)
  • Received : 2014.05.30
  • Accepted : 2014.06.17
  • Published : 2014.06.28
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Abstract

The compressibility of fracture in naturally fractured reservoir is larger than the compressibility of matrix in rock, although the compressibility of a typical rock is very small. The effective compressibility including the fracture compressibility should be considered to predict oil recovery correctly. It is hard to quantify changes of fracture aperture and pore volume in reservoir without the effective compressibility. In this study, oil recovery is analyzed by commercial simulator concerning the fracture compressibility based on fracture properties. We found that the effective compressibility affects oil recovery with change of polymer flooding factors such as polymer molar weight, concentration and injection rate. The estimated cumulative oil production is smaller with the effective compressibility than without it. Also, bottomhole pressure decreases rapidly without considering effective fracture compressibility.

불균질한 자연균열 저류층에서 암체의 압축률은 매우 작은 값을 가지는 반면에 균열의 압축률은 상대적으로 큰 값을 갖는다. 균열의 압축률을 포함한 유효 압축률을 고려하지 않을 경우에는 균열의 간극 변화로 인한 공극 부피의 변화를 반영할 수 없기 때문에 정확한 오일 회수를 예측할 수 없다. 본 연구에서는 기존의 연구들에서 암체의 압축률만을 고려하여 오일 회수를 분석했던 것과 달리, 암체와 균열의 압축률을 모두 고려한 유효 압축률을 적용해서 오일 회수량을 분석하였다. 폴리머 공법에서 균열의 압축률이 폴리머의 주입에 미치는 영향을 이해하기 위해, 폴리머의 분자량, 농도, 주입속도에 따른 오일 회수량을 분석하였다. 유효 압축률을 고려할 경우 폴리머 분자량, 농도, 주입속도가 높아질수록 유효 압축률을 고려하지 않은 경우가 고려한 경우보다 누적 오일 생산량이 높게 나타났다. 또한 공저 압력의 경우에도 유효 압축률을 고려하지 않은 경우가 고려한 경우보다 빠르게 급감하여 오일 생산량에 영향을 주는 것을 확인할 수 있다.

Keywords

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