Low-residue salt-tolerant fracturing fluid preparation method

Abstract

The invention relates to a low-residue salt-tolerant fracturing fluid preparation method, and belongs to the technical field of fracturing fluid preparation. The preparation method comprises: mixing dimethylallylamine, chloroacetic acid and a sodium hydroxide solution to obtain a light yellow viscous liquid, introducing chlorine gas into the light yellow viscous liquid, carrying out heating distillation, adding anhydrous ethanol, cationic hydroxyethyl cellulose, river sand and an encapsulation gel breaker, and carrying out a stirring reaction to obtain the low-residue salt-resistant fracturingfluid. According to the present invention, the amphoteric cellulose ether in the fracturing fluid can effectively weaken and prevent the free water molecules in the aqueous fracturing fluid from hydration on the surface of the fracturing fluid particles and the pigment so as to improve the hydration dispersibility of the guar gum, completely break the gel and reduce the residue; the used guar gumcan improve the static viscosity of the aqueous fracturing fluid by rapidly hydrating with the water molecules through hydrogen bonding; and a large number of the cationic groups have good repellencyto the metal cation, such that the fracturing fluid has good salt-tolerant stability and has broad application prospects.

Description

technical field

[0001] The invention relates to a preparation method of a low-residue salt-resistant fracturing fluid, which belongs to the technical field of fracturing fluid preparation. Background technique

[0002] Fracturing is one of the main production stimulation measures for low-permeability oil and gas reservoirs. It is a method of forming cracks in oil and gas layers by using hydraulic action, also known as oil and gas layer hydraulic fracturing. People use the surface high-pressure pump group to inject high-viscosity liquid into the well with a displacement that greatly exceeds the energy absorbed by the formation. With the formation of high pressure near the bottom of the well, after the pressure exceeds the ground stress near the bottom of the well and the expansion strength of the rock, the fracture extends forward and fills the proppant in the fracture, and a sufficient length can be formed in the formation after the pump is stopped. , sand-filled cracks of ...