Successful Application of Self-propping Fracturing Fluid System in Volume Fracturing of Tight Reservoir

The volume fracturing technology characterized by large-scale, large displacement, segmented multi cluster perforation and high slick water ratio has effectively developed tight reservoirs. However, tight oil reservoirs generally have deep burial depth, high fracture pressure gradient, poor sand carrying capacity of slippery water system, short migration distance of proppant, and high potential risk of overpressure and sand plugging,. In view of this phenomenon, a self-supporting fracturing fluid system with reverse phase transformation characteristics is developed, which includes immiscible self-supporting fracturing fluid and channel fracturing fluid. After the self-supporting fracturing fluid is injected into the formation fracture, it changes into high-strength self-supporting solid phase when heated. The channel fracturing fluid effectively flows back after occupying the rest of the fluid space, and finally forms the self-supporting fracture with high conductivity. In January of 20, 110 m3 self-supporting fracturing fluid system was added to well Y-24 of tight sandstone reservoir during fracturing, and then quartz sand and ceramsite were injected with slippery water, with a total injection volume of 1208.8 m3 And a total support volume of 131 m3/d. In the initial stage of backflow, the daily crude oil production of this well is 12.3 m3/d. After fracturing for 365 days, which is still higher than 2 m3/d. the stimulation effect is obviously better than that of two test wells with the same scale fracturing in the same block. Self supporting fracturing fluid system has the advantages of easy injection, no residue, adjustable phase change temperature, arbitrary injection displacement and support concentration. This system is suitable for a variety of reservoir and wellbore structures, and the construction technology is simple, which can completely solve the proppant placement problem and effectively improve the “fracture controlled reserves”. This practice puts forward new ideas and methods for unconventional reservoir reconstruction.