The Utility Model Relates to Indoor Research and Field Application of Polymer Multifunctional Fracturing Fluid Suitable for Tight Gas Reservoirs

Fracturing is an important means to increase production in low-permeability reservoirs. With the development of fracturing technology in unconventional reservoirs, the demand for fracturing is increasing. However, the tight gas reservoir in Jidong oilfield is located in loess plateau, and fresh water resources are relatively scarce. With the expansion of fracturing scale, the difficulty and cost of work increase exponentially. In order to effectively reduce the cost of fracturing measures and the effect of safeguard measures, research was carried out on synthetic polymer type variable viscosity fracturing fluid suitable for tight gas reservoirs, indoor research and development of polymer, polymerization can form a spatial reversible network structure system. Under the condition of low thickening agent, the performance of the system such as temperature resistance, shear resistance, rubber breaking and waterproof lock was analyzed and studied. A synthetic polymer type variable viscosity fracturing fluid system suitable for tight gas reservoirs was formed. The fracturing liquid system can completely break the glue in 60 min at a low temperature of 10 ℃. At 50 ℃ for 90 min, the 100s-1 viscosity reaches 52.6 mPa.s, and the interfacial tension is less than 1 mN/m, which realizes rapid backflow and has little pollution to the formation. The fracturing fluid system has been used in 260 Wells with a 100% success rate.