Fracturing method for artificial crack of low damage and high flow conductivity of coal-bed gas well

Abstract

The invention provides a fracturing method for an artificial crack of low damage and high flow conductivity of a coal-bed gas well. The fracturing method comprises the steps that (1) a thickener is prepared; (2) fracturing liquid is injected through a high pressure pump; (3) the viscosity of the fracturing liquid is increased; (4) a proppant is added; (5) the viscosity of the fracturing liquid is reduced; (6) the viscosity of the fracturing liquid is increased, and the concentration of the proppant is increased; and (7) working is finished. The fracturing method has the characteristics that the viscosity of the fracturing liquid can be controlled in real time in the whole process of coal bed fracturing construction, the success rate of construction can be effectively improved, reservoir damage is reduced especially for the low young modulus property of a coal bed, high sand ratio adding of coal bed fracturing can be realized by controlling the viscosity of the fracturing liquid, and the flow conductivity of the artificial crack in the coal bed is improved.

Description

technical field [0001] The invention relates to the field of fracturing and production stimulation transformation in coalbed methane exploitation, in particular to a fracturing method for artificial fractures of coalbed methane wells with low damage and high conductivity. Background technique [0002] Coal seams generally have the characteristics of looseness, weak cementation, and high fluid loss. The conventional fracturing method is to use activated water, clean fracturing fluid, and guar gum fracturing fluid system to achieve sand fracturing of coal seams. [0003] The active water fracturing fluid system has the characteristics of low damage, but due to the low viscosity of the system, the filtration loss in the coal seam is large, and the fracture creation efficiency is low, resulting in problems such as high ground construction pressure, large fluctuations, and easy sand plugging during construction. Seriously affect the transformation effect. [0004] The clean frac...

AI Technical Summary

Problems solved by technology

[0006] At present, active water fracturing fluid is widely used, but due to the low viscosity of active water, the average sand ratio is generally low, and the Young’s modulus of the coal seam is small, and the construction proppant with low sand ratio is easy to embed in the coal seam after the artificial fracture is closed. , leading to poor flow conductivity of artificial fractures, which cannot achieve the expected production stimulation effect

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