Analysis of Dry CO2 Fracturing Technology for Efficient Development of Shale Gas Reservoirs

Shale gas resource potential is tremendous in China, the recoverable resources are 25.08 x10(12) m(3). However, they mainly located in the arid area with lack of water, and clay mineral content of shale reservoir is higher, traditional water-based fracturing fluid used for shale gas development has defects of high water consumption and the serious damage to reservoir, so it is not suitable for stimulation of shale gas reservoir in China. Dry CO2 fracturing is a fracturing technology using liquid CO2 as a carrier fluid. For the water sensitivity low permeability tight sandstone gas reservoir, the stimulation effect of this technology is remarkable. CO2 fracturing technology is proposed innovatively to apply to development of shale gas reservoirs in China with the advantage of no water consumption, no damage to the reservoir and promoting CH4 desorption. CO2 fracturing technology applied to shale gas reservoir development involves many key scientific problems. The future research work should mainly focus on three aspects. Firstly, screening and optimizing CO2 fracturing fluid formulation system suitable for shale gas reservoir of China; Secondly, studying binary CH4-CO2 adsorption and desorption on shale; Thirdly, developing CO2 fracturing matching techniques of low cost.