Timed breaking release type microcapsule gel breaker and preparation method thereof

Abstract

The invention discloses a timed breaking release type microcapsule gel breaker. The timed breaking release type microcapsule gel breaker is composed of a core material and a membrane material. The membrane material comprises aniline or pyrrole, stearyl amine and petroleum resin. The microcapsule gel breaker comprises the following components in percentages by weight: 94-96% of core material, 0.5-2% of aniline or pyrrole, 0.5-1% of stearyl amine and 1-5% of petroleum resin. According to the microcapsule gel breaker disclosed by the invention, the initial release time can be regulated according to construction requirements, and the microcapsule gel breaker has the characteristics of being high in coating rate, high-temperature-resistant, high-pressure-resistant, high in degree of mineralization, strong acid and alkali-resistant, high in shearing property and the like.

Description

technical field [0001] The invention belongs to the fields of oil field development, new materials, and chemical engineering, and in particular relates to a high-efficiency preparation method of a timed rupture-release microcapsule breaker. Background technique [0002] Water-based fracturing is one of the key technologies for enhancing oil recovery in oilfields at home and abroad. During water-based fracturing, the polymer gel in the fracturing fluid is used to carry proppant, control fluid loss, and maintain fluid viscosity. After the fracturing operation is completed, the above-mentioned polymers need to be completely broken and flowback under the action of the breaker to reduce the damage to the oil well. Commonly used gel breakers include water-soluble inorganic salts such as ammonium persulfate, potassium persulfate, and potassium permanganate. However, if the above gel breakers are added too early or too much, the viscosity of the fracturing fluid will decrease rapid...

AI Technical Summary

Problems solved by technology

However, there are the following problems in the actual application process: 1) The stress of the microcapsule breaker is not completely consistent when the formation is closed, so the degree of rupture of the microcapsule membrane material is also inconsistent, which eventually leads to different release degrees , and some even cannot break, seriously affecting the gel-breaking effect of fracturing fluid and affecting the conductivity of oil layer fractures; 2) Microcapsule gel-breakers are easily affected by temperature, pressure, pH value, salinity, Influenced by factors such as shear force, it will be released prematurely, causing the fracturing viscosity to drop rapidly, affecting the fracturing ability of the fracturing fluid during construction, and even causing early sand removal, resulting in construction failure; 3) Using the above method and membrane The microcapsule breaker prepared by the material is released slowly, so the viscosity of the fracturing fluid begins to decrease slowly during the injection process, which will also affect the construction effect of the fracturing fluid

Images