Low-harm fracturing fluid and preparation method thereof

Abstract

The invention relates to a low-harm fracturing fluid and a preparation method thereof. In the prior art, the fracturing fluid can produce much residue, and therefore bringing residue harm and other adverse effects on the fracturing effect. In the technical scheme provided by the invention, the components of the low-harm fracturing fluid and the content of each component are as follows: 0.15 to 0.2 percent of natural vegetable gum thickening agent, 0.3 to 0.5 percent of viscoelastic surfactant, 0.4 to 0.8 percent of cross-linking agent and the balance of water; the viscoelastic surfactant is unsaturated fatty acid salt which has viscoelasticity under the alkaline condition; and the cross-linking agent is conventional boron cross-linking agent. The invention has the following characteristics: (1) since the usage of natural vegetable gum is reduced, residue is reduced; (2) the amount of the residue of the guar gum can be reduced to 13 percent of the usage of the guar gum, so that the harm of the fracturing fluid on crude oil reservoirs can be decreased; and (3) compared with the cost of the clean fracturing fluid, the cost of the low-harm fracturing fluid is lower.

Description

technical field [0001] The invention relates to the technical field of fracturing fluid for oil exploitation, in particular to a low-damage fracturing fluid and a preparation method thereof. Background technique [0002] Fracturing fluid plays a very important role in oil extraction. Guar gum is currently the most common and easy-to-use fracturing fluid configuration material. Since guar gum belongs to natural vegetable gum, the configured fracturing fluid will produce more residues. As a result, negative effects such as residue damage will be brought to the fracturing effect. Reducing the content of guar gum in the fracturing fluid is the most direct way to reduce the amount of residue, but in order to ensure the basic sand-carrying capacity of the fracturing fluid, the content of guar gum is usually kept above 0.4%. The residue damage produced at this concentration cannot be ignored. In order to reduce or eliminate residues, surfactant-based clean fracturing is in contin...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a low-cost and low-damage fracturing fluid with less residue and its preparation method, so as to overcome the problems of many residues and high cost in the prior art