Staged fracturing technology of proppant shielding and temporary plugging in shale gas horizontal wells

Abstract

The invention discloses a shale gas horizontal well proppant in-crack shielding and temporary plugging staged fracturing process. The process includes following steps: lowering a continuous oil pipe and a sand blasting perforation tool a layer section needing fracturing modification, performing multi-cluster perforation, and lifting up the continuous oil pipe and the perforation tool; setting highest safe pumping pressure on the ground, and conducting main fracturing to promote a reservoir to generate a size crack; after injection liquid quantity reaches 1600-1800m3, pumping a proppant section plug for temporary plugging; after the section plug used for sand filling enters a stratum hole, lowering injection displacement until a sand plug completely enters a stratum; if shaft pressure rises to the highest safe pumping pressure set on the ground, showing that shielding and plugging are successful; lowering the continuous oil pipe for multi-cluster perforation and main fracturing of the next section until fracturing of all sections is completed. Multi-cluster sand blasting perforation of the continuous oil pipe is combined with in-crack sand filling temporary plugging staged fracturing, so that the complex problems that a mechanical bridge plug and a perforation tool cannot be lowered due to casing deformation and hole shrinkage and the like can be solved effectively.

Description

technical field [0001] The invention relates to a shale gas horizontal well proppant fracture inner shield temporary plugging staged fracturing process, which is used for staged fracturing reconstruction of shale gas wells. Background technique [0002] At present, bridge plug segmentation technology is generally used in the fracturing stimulation of shale gas horizontal well reservoirs in the Sichuan Basin, and the injection method is bare casing fracturing. Under the influence of various factors such as formation dislocation caused by neotectonic movement, interwell interference, casing quality, etc., downhole complex situations such as casing deformation may occur, which brings huge risks and challenges to reservoir stimulation. In actual construction, due to the deformation of the inner casing in the wellbore, the diameter of the wellbore becomes smaller, and mechanical isolation cannot be used for cable transmission, clustered perforation and bridge plugging, which grea...

AI Technical Summary

Problems solved by technology

The present invention applies multi-cluster sandblasting and perforating of coiled tubing combined with sand filling in fractures for temporary plugging and segmental fracturing, which can effectively solve complex problems such as casing shrinkage and other problems that mechanical bridge plugs and perforating tools cannot be lowered.