Refracturing method by naturally selecting dessert temporary blocking size for horizontal well

Abstract

The invention discloses a refracturing method by naturally selecting dessert temporary blocking size for a horizontal well. The refracturing method comprises the steps that a well with certain geologic reserves is selected, and geological dessert areas of the whole horizontal well which needs to be subjected to refracturing are ruled again; a new rock mechanics crack initiation order is predicted;the dessert area with rich accumulation of oil and gas and with the best physical property is found, and a first fracture is pressed to be open; the first fracture is blocked through a temporary blocking agent, fracturing liquid is pumped into continuously, the pressure rises, the dessert area of the secondary grade is selected, and a second fracture is pressed to be open; multiple fractures of athird fracture, a fourth fracture and the like are sequentially pressed to be open, and fracturing of the multiple fractures with naturally selected desserts in a segment is realized; and meanwhile,the powder-like high-strength water-soluble temporary block agents are put into the fractures so as to form temporary blocking on the end of the main fracture, the net pressure in the fracture is increased, the micro-fracture which cannot crack originally is pressed to be open, or the new branch fracture is formed, and a larger transformation size is obtained. According to the refracturing method,the defect that a sleeve is deformed, and consequently, a downhole tool cannot be tripped into is effectively overcome, and recovering and increasing of the productivity of the horizontal well are facilitated.

Description

technical field [0001] The invention relates to the technical field of oil and gas field development, in particular to a method for horizontal well natural selection sweet spot temporary plugging volume repeated fracturing technology, which is used for repeated reconstruction of old horizontal wells. Background technique [0002] As domestic oil fields generally enter the stage of secondary or even tertiary oil recovery, the production of many horizontal wells in production has declined rapidly due to long-term exploitation, and it is difficult to stabilize production; Can be modified or the degree of modification is not enough, and the production capacity has not been tapped. In order to release the potential of these oil wells, it is necessary to refracture the oil wells to increase the production of old wells. Horizontal wells have been the mainstream wellbore model in recent decades. Stimulation and development of them are extremely efficient. Now the commonly used hori...

AI Technical Summary

Problems solved by technology

The commonly used horizontal refracturing method is the staged fracturing process of horizontal well double-sealed single-clamp dragging pipe string, but it is easy to cause complex downhole accidents; for some casing deformation, the method cannot be used in wells where tools cannot be lowered

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