Preparation method of microcapsule gel breaker for fracturing

Abstract

The invention provides a preparation method of a microcapsule gel breaker for fracturing, which is characterized in that a vibrator is arranged at the bottom of conventional fluidized bed equipment, and vibrates at a set frequency in the production process, so that the capsule core of each capsule is always in a moving state, and capsule core particles are in full contact with an outer coating material, thereby achieving the effects of tighter combination and more uniform coating. The leakage rate of the capsule gel breaker produced by the process is as low as 0.2%, the viscosity retention rate of the fracturing fluid measured by a standard method is more than or equal to 75%, the highest viscosity retention rate reaches 99.2%, the quality is stable, the degradation time of the gel fracturing fluid can be effectively controlled in field application, the damage of the fracturing fluid to an oil layer is reduced, and the production process is wide in adaptability and is not influenced by the environment. The application of preparing the capsule gel breaker from different raw materials and formulas can be met.

Description

technical field [0001] The invention relates to a preparation method of a microcapsule gel breaker for fracturing, in particular to a process for producing microcapsules through a vibrating fluidized bed. Background technique [0002] Fracturing is an important measure to increase the production of low-permeability oil and gas, and the polymer fracturing fluid used in the construction must be completely broken to achieve a good fracturing effect, but in the process of fracturing construction, the fracturing fluid It must also maintain a certain viscosity. In order to achieve this goal, the researchers introduced the microcapsule technology in the pharmaceutical field, using the gel breaker as the core material, and using the slow-release capsule wrapping materials used in the pharmaceutical field as the wall material to achieve Gel breaking slow release of gel breaker. [0003] At present, there are mainly two types of capsule preparation techniques: one is the direct mixin...

AI Technical Summary

Problems solved by technology

[0004] After many years of research and practice, researchers of the present invention have found that these two types of production processes have certain defects, mainly including three points: the first is that the product quality fluctuates greatly, and the same process has a large difference in product quality between different batches; The outer layer of the obtained product is loose; the third is that the capsule leakage rate is high and unstable, and the direct impact is that the most important technical index of the product-the viscosity stability rate of the fracturing fluid is unqualified

In order to reduce the leakage rate during the preparation process, methods such as increasing the amount of coating solution and prolonging the coating time may be adopted, but this method not only increases the production cost, but also easily leads to a decrease in the release rate and affects the gel breaking effect