Huff-n-Puff Gas Injection Performance in Shale Reservoirs: A Case Study From Duvernay Shale in Alberta, Canada

Compositional Simulation of Geological and Engineering Controls on Gas Huff-n-Puff in Duvernay Shale Volatile Oil Reservoirs, Canada

“…Horizontal drilling and multi-stage hydraulic fracturing have facilitated to a large increase in shale oil production in North America through continuous drilling investment in recent years. However, the ultimate oil recovery of shale oil reservoirs is usually less than 10%, which is much lower than that of conventional reservoirs [1][2][3][4][5][6].…”

“…With the increase of shale gas production and the falling of natural gas prices in North America, field trials and reservoir simulation have been conducted on natural gas huff-n-puff in shale reservoirs. Hamdi et al [6] investigated the feasibility of huff-n-puff operations in the Duvernay shale, with a variety of injection fluids, and concluded that higher injection rates, shorter injection, soaking, and production times, and higher flowing pressures during the production cycle could result in higher recoveries by huff-n-puff. The simulated results by Hamdi et al suggest that the huff-n-puff process using rich gas can produce 30% higher cumulative oil production than using lean gas.…”

“…The volatile oil recovery factors achieved from primary production are much lower than those from the gas-condensate window, typically 5-10% of original oil in place. A previous study has indicated that huff-n-puff gas injection is one of the most promising EOR methods in the Duvernay shale volatile oil reservoirs [6]. Selection of the most realistic field trial horizontal well in Duvernay shale volatile oil reservoirs is crucial for the ultimate confidence of this EOR method and decision-making.…”

Recovery Mechanisms for Cyclic (Huff-n-Puff) Gas Injection in Unconventional Reservoirs: A Quantitative Evaluation Using Numerical Simulation

“…Tovar et al [18] used laboratory data to discuss the importance of vaporization and declared that it is the main recovery mechanism for gas injection EOR in organic rich shales. Hamdi et al [19] discussed the complex function of mass transfer and extraction processes related to a number of different potential mechanisms. Hoffman and Rutledge [20] compared the role of diffusion and advection for the oil-swelling mechanism using analytical models.…”

Phase Equilibrium in Shale Including Porous Media Effects

“…Interest of gas injection on shale reservoirs has increased in the past years since Huff-N-Puff studies have shown that there is a high potential to improve oil recovery on the current wells (Meng et al 2015, Li et al 2016, Hamdi et al 2018, Wang and Yu 2019, Ganjdanesh et al 2019. Here, we have used the tool developed by Sandoval et al (2018) to further investigate depletion scenarios through Differential Liberation (DL) and constant volume depletion (CVD) tests; and gas injection of methane using 1D-slimtube simulations.…”