Treatment method of fracturing backflow fluid

Abstract

The invention discloses a treatment method of fracturing backflow fluid. The method comprises the following steps of 1), recovering the fracturing backflow fluid into a recovery tank, carrying out physical treatment on the fracturing backflow fluid recovered in the recovery tank, removing a mechanical impurity, a suspended solid impurity and an oil stain impurity in the fracturing backflow fluid,and preliminarily carrying out water quality detection analysis on the fracturing backflow fluid subjected to the physical treatment; and 2), according to a pH value obtained in the step 1), regulating by using a PH regulator, regulating the PH value to be between 6 and 9, then, carrying out gel breaking treatment on the fracturing backflow fluid finished in the regulation of the PH value by adopting a 0.002mg / L to 80mg / L of gel breaker, and carrying out oxidation treatment by adopting a 0.01mg / L to 200mg / L of oxidant after the gel breaking treatment is complete, so as to obtain the fracturingbackflow fluid which is complete in gel breaking and is further decreased in viscosity. By using the treatment method of the fracturing backflow fluid, which is provided by the invention, the backflow fluid is recovered and reutilized; not only can the problem that a water resource is short for the fracturing construction in a northwest region be relieved, but also the emission amount of waste fluid can be reduced at the same time; and the environment-friendly and energy-saving development of an unconventional oil-gas field is realized.

Description

technical field [0001] The invention relates to the technical field of oil field fracturing stimulation and injection, in particular to a treatment method for fracturing flowback fluid. Background technique [0002] Due to the shortage of water resources in Northwest my country, fracturing is an important means of reservoir stimulation in the production stimulation of low-permeability oil and gas reservoirs. Among them, water-based fracturing is widely used in fracturing construction, and the water consumption of a single horizontal well is generally 8000-30000m 3 , if things go on like this, it is difficult to meet the water source requirements for large-scale volume fracturing. [0003] At the same time, a large amount of flowback fluid is produced after oil and gas volume fracturing. After the fracturing operation is completed, 15-80% of the flowback fluid is discharged to the ground, which will cause great damage to the environment. The flowback liquid has high COD val...

AI Technical Summary

Problems solved by technology

Among them, water-based fracturing is widely used in fracturing construction, and the water consumption of a single horizontal well is generally 8000-30000m 3 , if things go on like this, it is difficult to meet the water source requirements for large-scale volume fracturing

[0003] At the same time, a large amount of flowback fluid is produced after oil and gas volume fracturing. After the fracturing operation is completed, 15-80% of the flowback fluid will be discharged to the ground, which will cause great damage to the environment.

The flowback liquid has high COD value, high chroma, high content of suspended solids, and contains high metal ions, organic matter, chlorine radicals and other pollutants. If it is not disposed of properly, it will pollute the environment.

It is difficult, expensive and costly to make the fracturing flowback fluid harmless

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