An experimental study on huff-n-puff gas injection to enhance condensate recovery in shale gas reservoirs

Xingbang Meng, Yang Yu, James J. Sheng, Marshall Watson, Fersheed Mody

Research output: Chapter in Book/Report/Conference proceedingConference contribution

16 Scopus citations

Abstract

Due to the low gas price, production of liquid oil has attained more attention. Producers are seeking to maximize liquid oil production from gas-condensate reservoirs. However, once a shale gas-condensate reservoir is produced, by reservoir depletion, the pressure near the well will decrease below the dew point pressure because of its ultra-low permeability. Then liquid condensate forms. The liquid condensate accumulates near a wellbore forming condensate banking, thus gas productivity is decreased. And the low-saturation condensate in the formation could remain unproduced. To solve the above problems, this paper proposes huff-n-puff gas injection to boost the reservoir pressure near the production wells. It is expected that the pressure increase during the huff period will "vaporize" the liquid condensate which will be produced during the puff period. Experiments were conducted to investigate this mechanism. In the experiments, a core was initially saturated with a gas-mixture. Then huff-n-puff cycles were repeated. The CT scanner was used to analyze the fluid distribution in the core, and by using CT numbers, saturation of condensate would be determined. The effects of these parameters were studied: 1) huff-n-puff cycles, 2) soaking time. The experimental results showed that the vaporization mechanism could reduce the liquid dropout. The results also show that injection pressure does not significantly change oil recovery when the pressure was higher than the dew point pressure, and soaking time slightly affect condensate recovery. The experimental results indicate that huff-n-puff gas injection could be an effective approach to enhance gas-condensate recovery in shale gas reservoirs.

Original languageEnglish
Title of host publicationSociety of Petroleum Engineers - Unconventional Resources Technology Conference, URTeC 2015
PublisherSociety of Petroleum Engineers
ISBN (Electronic)9781613994337
StatePublished - Jan 1 2015
EventUnconventional Resources Technology Conference, URTeC 2015 - San Antonio, United States
Duration: Jul 20 2015Jul 22 2015

Publication series

NameSociety of Petroleum Engineers - Unconventional Resources Technology Conference, URTeC 2015

Conference

ConferenceUnconventional Resources Technology Conference, URTeC 2015
CountryUnited States
CitySan Antonio
Period07/20/1507/22/15

Fingerprint Dive into the research topics of 'An experimental study on huff-n-puff gas injection to enhance condensate recovery in shale gas reservoirs'. Together they form a unique fingerprint.

  • Cite this

    Meng, X., Yu, Y., Sheng, J. J., Watson, M., & Mody, F. (2015). An experimental study on huff-n-puff gas injection to enhance condensate recovery in shale gas reservoirs. In Society of Petroleum Engineers - Unconventional Resources Technology Conference, URTeC 2015 (Society of Petroleum Engineers - Unconventional Resources Technology Conference, URTeC 2015). Society of Petroleum Engineers.