Dual-function explosive pre-crosslinking gel particle for profile control and deep fluid flow diversion

Abstract

The invention relates to a dual-function explosive pre-crosslinking gel particle for profile control and deep fluid flow diversion. The pre-crosslinking gel particle for the profile control and the deep fluid flow diversion provided in the invention is a gel particle obtained by polymerizing and crosslinking a monomer, a stable crosslinking agent and an unstable crosslinking agent by an initiator to obtain a body gel, drying the gel and grinding the gel. The gel particle has a core-shell structure, wherein the stable crosslinking agent is polymerized and crosslinked with parts of the monomer to form the stable crosslinking core, and the unstable crosslinking agent is polymerized and crosslinked with parts of the monomer at the outside of the stable crosslinking gel core to form the unstable crosslinking gel coating shell. When the gel particle provided in the invention is applied to the oil reservoir exploitation, the dual effect of the profile control and the deep fluid flow diversion can be realized, and concentrations of the stable crosslinking agent and the unstable crosslinking agent can be adjusted to control the explosion time of the pre-crosslinking gel particle, so a purpose for controlling the working period can be reached.

Description

technical field [0001] The invention relates to a gel particle used in the water plugging operation of petroleum exploitation, in particular to a blasting pre-crosslinked gel particle with dual functions of profile control and deep liquid flow diversion, which belongs to the technical field of petroleum exploitation. Background technique [0002] With the continuous development of oilfields, the heterogeneity of reservoirs is becoming more and more serious. A large amount of injected water scours, swelling and dissolution of clay and cement in oil layers, migration of particles, and aggravation of sand production will cause further deterioration of geological heterogeneity. . During the development process, the following problems often appear: prominent plane contradictions, plane injection water rushes along the high-permeability zone to form water channels; prominent interlayer contradictions, uneven production and suction profiles, and single-layer breakthroughs in the ve...

AI Technical Summary

Problems solved by technology

During the development process, the following problems often appear: prominent plane contradictions, plane injection water rushes along the high-permeability zone to form water channels; prominent interlayer contradictions, uneven production and suction profiles, and single-layer breakthroughs in the vertical direction; high viscosity of underground crude oil, oil-water High viscosity ratio, serious viscous fingering phenomenon, etc.

In recent years, although tertiary oil recovery measures such as polymer flooding have achieved good results, there are still problems such as high cost of oil displacement and difficulty in field implementation; In oil reservoirs, there are still serious problems of channeling in some wells, which affects the effect of polymer injection. Moreover, due to the limitations of the polymer itself, the effective viscosity loss in high-temperature and high-salinity formations is very large, which often cannot be reached. to the intended purpose

ASP flooding technology has gradually been widely used in Daqing and other old oilfields. The use of surfactants to reduce interfacial tension greatly reduces capillary force, and oil and water achieve miscible flow, thus starting the low permeability reservoir. Residual oil, but ASP flooding technology and polymer flooding have similar problems: shear thinning, affected by reservoir conditions, and both polymer flooding and ASP flooding will pollute oil-bearing low-permeability layers, making subsequent water flooding unable to achieve best results

Flexible particles can form dynamic plugging in deep reservoirs, but for fractures and ultra-high permeability layers caused by high-intensity water scour near the wellbore, high-strength plugging agents must be used for anti-channeling operations, otherwise flexible diverting agents will not improve recovery The effect cannot be maximized

[0007] To sum up, so far, profile control and deep liquid flow diversion cannot be carried out simultaneously in the water plugging and profile control technology of oil production, and no existing technology can solve this problem.

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