Clean fracturing fluid with liquid thickening agent and preparation method thereof

Abstract

The invention relates to a clean fracturing fluid with a liquid thickening agent and a preparation method thereof. The problem of dissolution of the thickening agent is one of the problem which causes that the clean fracturing fluid is difficult to widely use in the using process of the clean fracturing fluid, and most of most of viscoelastic surface active agents are generally difficult to fast dissolve under the condition of room temperature. The preparation method comprises the following steps of: mixing high-melting point unsaturated fatty acid and low-melting point unsaturated fatty acid according to the proportion of 1:(2-1):3 to prepare an unsaturated fatty acid thickening agent; preparing the mixed water solution of sodium hydroxide and potassium chloride, wherein the mass percent is respectively as follows: 0.8%-1.2% and 2.2%-3%; mixing the unsaturated fatty acid thickening agent and the mixed water solution at a ratio of 2.4:(100-3):100 under the condition of vigorous stirring to prepare a product. Compared with other clean fracturing fluids of the surface active agents, the clean fracturing fluid disclosed by the invention is more convenient in process when in use because the thickening agent is in a self liquid state and has good solubility of components. According to the invention, the adopted thickening agent is micromolecular and less in formation damage, so that the oil recovery efficiency is easier to increase.

Description

technical field [0001] The invention relates to a fracturing fluid in petroleum exploitation, in particular to a clean fracturing fluid using a liquid thickener and a preparation method thereof. Background technique [0002] Water-based fracturing fluid is a production stimulation measure commonly used before crude oil exploitation. In order to obtain a certain viscoelasticity for fracturing fluid, thickener is an indispensable raw material. Currently, the most used thickener is water-soluble Sexual polymers. However, in order to reduce the damage to the formation, the viscoelastic surfactant with small molecular weight has been paid more and more attention, and it is called clean fracturing fluid. [0003] During the use of clean fracturing fluids, the dissolution of thickeners is one of the problems that make it difficult to widely use clean fracturing fluids. Most of the currently used viscoelastic surfactants are solid powders, which need to be uniformly dispersed in ...

AI Technical Summary

Problems solved by technology

In order to uniformly disperse the small molecule thickener in water, certain measures need to be taken, but most of these measures will result in an increase in the construction process or a decrease in the viscoelastic properties of the fracturing fluid

If the method of heating to promote dissolution will increase the number of on-site equipment, the method of preparing the concentrated solution in advance will cause a large increase in the volume of the thickener due to the solubility of the surfactant, which will cause inconvenience in transportation. Use organic solvents to prefabricate high-concentration solutions The method will cause damage to the viscoelasticity of the fracturing fluid due to the intervention of organic solvents