A comparative experimental study of gas injection in shale plugs by flooding and huff-n-puff processes

Eagle Ford core samples were used in this study and saturated with shale oil. Using N2 as the gas source, gas injection tests were operated on the same plug orderly by both modes under the same operating conditions. The sensitivity of soaking time on the huff-n-puff performance was evaluated. Lab-scale numerical models were built to simulate flooding and huff-n-puff processes and to history match the experimental data. It was found that optimization design of huff-n-puff is important to achieve the maximum oil recovery. The results show that the huff-n-puff possess can achieve a higher oil recovery than the flooding process.