Self-supporting fracturing fluid system for fracture network stimulation in unconventional reservoirs

Abstract

The present disclosure discloses a self-supporting fracturing fluid system used for fracturing of unconventional reservoirs with fractured network sections, the self-supporting fracturing fluid system comprising mutually immiscible self-supporting fracturing fluid in fractured network sections and fracture network section channel pressure A fracturing fluid, the self-supporting fracturing fluid of the fractured mesh section includes the following components: 10-40 parts of polyphenylene ether, 10-20 parts of dicumyl peroxide, 10-50 parts of triallyl isopropyl alcohol Cyanurate, 40-90 parts of styrene, 1-10 parts of surfactant, and 50-500 parts of solvent; the fractured mesh segment channel fracturing fluid includes the following components: 1-50 parts of resistance reduction agent, 10-100 parts of potassium chloride, 100-900 parts of clean water, 1-10 parts of quaternary ammonium salt cationic polymer, 1-100 parts of polyethylene glycol, 5-500 parts of dodecyl sulfate sodium. The present disclosure can greatly improve the conductivity of fractures in the main fracture section of volume fracturing, and eliminate the risk of sand plugging.

Description

technical field [0001] The disclosure belongs to the technical field of oilfield development, and in particular relates to a self-supporting fracturing fluid system used for reforming fractured network sections of unconventional reservoirs. Background technique [0002] The production increase of oil and gas fields can be achieved by injecting fracturing fluid into the reservoir to recreate fractures, that is, using the ground high-pressure pump set to squeeze liquid with a certain viscosity ( fracturing fluid) to gradually increase the pressure in the wellbore. When the pressure increases above the fracture pressure of the reservoir, the reservoir will form one or more main fractures at the proximal end (near the source of the fracturing fluid squeeze), and force the formation of secondary fractures at the far end and laterally of the main fractures. Fractures, and continue to branch on the secondary fractures to form secondary secondary fractures, and finally form a compl...

AI Technical Summary

Problems solved by technology

The construction technology of alternately injecting slick water is relatively complicated and the efficiency is low

[0007] (2) The utilization rate of complex fractures after fracturing is low, and the volume of stimulation is insufficient

[0008] Since the fractures formed in the fracture network segment are secondary fractures and secondary secondary fractures, these fractures have irregular shapes, high complexity, small opening (fracture width), and are far away from the main fractures, so it is difficult for proppant to enter, resulting in many fractures. The fractures opened cannot be effectively filled. After fracturing, many fractures are gradually closed under the closing pressure, so the total stimulated volume is insufficient.

[0009] (3) The diversion capacity is low, and the increase in production capacity is limited

[0010] Due to the poor sand-carrying capacity of slick water, only silt and silt can be carried to add sand, and the average sand ratio can only be controlled at 3-5%, so the conductivity of sand-filled cracks is greatly limited

The conductivity of these sand-filled fractures is not enough for the exploitation of unconventional natural gas, and it is far from meeting the demand of unconventional oil resources for fracture conductivity

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