Phase change fracturing fluid system for phase change fracturing

Patent metadata

Field	Value
Publication number	US-10364388-B2
Application number	US-201615775009-A
Country	US
Kind code	B2
Filing date	Sep 20, 2016
Priority date	Jul 7, 2016
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

The present invention discloses a phase change fracturing fluid system for phase change fracturing, including the following components in percentage by weight: 10%-40% of supramolecular construction unit, 0-40% of supramolecular function unit, 0.5%-2% of surfactant, 0-5% of inorganic salt, 0.5%-2% of oxidizing agent, 0-2% of cosolvent and the remaining of solvent. The supramolecular construction unit is melamine, triallyl isocyanurate, or a mixture thereof. The supramolecular function unit is vinyl acetate, acrylonitrile, or a mixture thereof. The solvent is methylbenzene, ethylbenzene, o-xylene, m-xylene or p-xylene. In the fracturing construction process, a conventional fracturing fluid is used for fracturing a formation first; the phase change fracturing fluid is then injected into the formation, or the phase change fracturing fluid and other fluids which cannot be subjected to phase change are injected into the formation together.

First claim

What is claimed is:

1. A phase change fracturing fluid system for phase change fracturing, comprising:
a supramolecular construction unit of 10%-40% by weight,
a supramolecular function unit of >0% and ≤40% by weight,
a surfactant of 0.5%-2% by weight,
an inorganic salt of >0% and ≤5% by weight,
an oxidizing agent of 0.5%-2% by weight,
a cosolvent of >0% and ≤2% by weight, and
a solvent of a remaining ratio by weight; and wherein
the supramolecular construction unit is a triallyl isocyanurate;
the supramolecular function unit is a vinyl acetate, an acrylonitrile, or a mixture of the vinyl acetate and the acrylonitrile.

2. The phase change fracturing fluid system for phase change fracturing according to claim 1 , wherein the surfactant is one or more selected from the group consisting of sodium dodecylbenzenesulfonate, and cetyl trimethylammonium bromide.

3. The phase change fracturing fluid system for phase change fracturing according to claim 1 , wherein the inorganic salt is one or more selected from the group consisting of sodium phosphate, calcium chloride, and magnesium chloride.

4. The phase change fracturing fluid system for phase change fracturing according to claim 1 , wherein the oxidizing agent is a hydrogen peroxide, an ammonium persulfate, or a sodium dichromate.

5. The phase change fracturing fluid system for phase change fracturing according to claim 1 , wherein the cosolvent is a polyethylene glycol, a polyvinyl pyrrolidone, or a mixture of the polyethylene glycol and the polyvinyl pyrrolidone.

6. The phase change fracturing fluid system for phase change fracturing according to claim 1 , wherein the solvent is a toluene, an ethylbenzene, an o-xylene, a m-xylene or a p-xylene.

Assignees

• Univ Southwest Petroleum

Inventors

• Zhao Liqiang
• Yang Yong
• Du Guangyan
• Yu Donghe
• Du Juan
• Che Hang
• Luo Zhifeng
• Liu Guohua
• Pei Yuxin
• Li Nianyin
• Liu Pingli
• Xu Kun

Classifications

• C09K8/64 Primary

  Oil-based compositions · CPC title

• C09K8/88

  macromolecular compounds · CPC title

• E21B43/26 Primary

  by forming crevices or fractures · CPC title

• C09K8/80

  Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open · CPC title

• C09K8/68

  containing organic compounds · CPC title