Fracturing method of reservoir

Abstract

The invention relates to a fracturing method of a reservoir. The fracturing method comprises the steps that a first agent, a second agent and a third agent are sequentially added into a stratum; the first agent comprises one or a combination of at least two of mud acid, multi-hydrogen acid and organic acid; the second agent is liquid carbon dioxide; the third agent comprises water-based fracturing fluid and a propping agent; by adopting a specific agent treatment mode, treatment of the total wave and the volume of the reservoir is achieved, a fracture network is constructed in a near-wellbore area, and the minimum main stress of the near-wellbore area is eliminated; the water-based fracturing fluid constructs a main fracture with the high flow conductivity in a far-wellbore area, so that the fracture extends to the deep part of the reservoir, the volume of the fracturing wave is further expanded, and a powerful guarantee is provided for continuous high and stable yield of a subsequent oil and gas well; and the liquid carbon dioxide in the middle section plays a role in promoting flowback and supplementing energy.

Description

technical field [0001] The invention relates to the field of oilfield exploitation, in particular to a reservoir fracturing method. Background technique [0002] At present, with the upgrading of domestic industry, the demand for oil and gas resources, especially natural gas, is further increasing. However, my country's unconventional natural gas resources are mainly tight sandstone gas and shale gas, which are difficult to exploit. Hydraulic fracturing technology is a method that must be adopted after the drilling and completion of natural oil and gas wells. Hydraulic fracturing sand filling is used to create artificial fractures in natural gas reservoirs, and sand filling maintains high conductivity of fractures, so that oil and gas wells can achieve higher productivity. Level. [0003] However, there are technical disadvantages in the application of conventional hydraulic fracturing to natural gas reservoirs. No matter whether the natural gas reservoir is tight sandstone...

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Problems solved by technology

[0008] In view of the problems existing in the prior art, one of the purposes of the present invention is to provide a method for fracturing reservoirs, which solves the problems of less clogged gaps and unreasonable distribution of reservoirs through a coordinated coordination system, and creates complex fractures and fractures. Expand the main fracture, and the injection slug position of liquid carbon dioxide can improve the flowback of the subsequent injected water-based fracturing fluid, effectively improve the conductivity of the reservoir, and achieve the goal of high and stable production of oil and gas wells