Soluble temporary blocking material for well fracturing and preparation method of soluble temporary blocking material for well fracturing

Abstract

The invention discloses a soluble temporary blocking material for well fracturing and a preparation method of the soluble temporary blocking material for well fracturing. The soluble temporary blocking material is a polymer prepared from, by mass, 25-30% of C4-C6 dicarboxylic acids, 7-10% of 2-acrylamide-2-methyl propanesulfonic acid, 20-25% of C4-C7 polyols, 5-8% of monohydric alcohol with a single benzene ring structure, 0.08-0.15% of an initiator, 1.5-2% of sodium hydroxide and 30% of distilled water. The soluble temporary blocking material is capable of dissolving completely without residual solids in environments of fracturing fluids at different temperatures.

Description

technical field [0001] The invention relates to the technical field of oil and gas well fracturing materials, in particular to a soluble temporary plugging material for oil and gas well fracturing and a preparation method thereof. Background technique [0002] my country's low-permeability oilfields are rich in petroleum geological reserves, and their resources account for about 30% of the country's total petroleum resources. Among the proven reserves, low-permeability oil reservoirs account for more than two-thirds of the country's reserves, and the development potential is huge. Although most low-permeability reservoirs have a large increase in production after fracturing, the production is still not high. In recent years, major oilfields have adopted multi-fracture technology or fracture diversion technology in the fracturing operation to intensify efforts to stimulate low-permeability reservoirs and maximize reservoir production. Steering fracturing technology is based ...

AI Technical Summary

Problems solved by technology

In addition, polymers with polyacrylamide as the main body are also used as temporary plugging agents, and their plugging strength and temporary plugging rate can also meet the requirements of on-site construction, but after degradation, they have high viscosity, which makes the fracturing fluid Increased viscosity is not conducive to flowback after construction, and will cause greater damage to the formation

[0005] The existing various temporary plugging agents have certain temporary plugging performance but also have their own defects. The release of inorganic salts during the dissolution process of the system composed of inorganic salts will cause permanent blockage of the formation, which is not conducive to later oil and gas production; cross-linking Cross-linked polymers need to be added with a gel breaker after construction to break the gel. In construction operations that require a long temporary plugging time, the construction cycle will be increased, resulting in increased costs. At the same time, the solubility of cross-linked polymers is poor, and some If the gel cannot be completely broken in the fluid, it will also stay in the formation and affect the later mining process; the dissolution of the PAM temporary plugging agent will increase the viscosity of the fracturing fluid, which is not conducive to the flowback of the fracturing fluid

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