A kind of preparation method and application of 2d nanosheet oil displacement agent

Abstract

The invention discloses a preparation method and application of a 2D nanosheet oil displacement agent, and relates to the technical field of oil displacement agents. The invention combines existing nanotechnology and microemulsion technology to improve the performance of modified MoS 2 The nanosheet system and microemulsion system are compounded to obtain a 2D nanosheet oil displacement agent system, so that nanosheets and surfactants are evenly distributed around the nano-oil core; during the oil displacement process, the nanosheets use comprehensive mechanisms such as wetting inversion and wedge penetration "Shovel off" the oil film on the wall surface into the bulk phase, and the nano-scale oil nuclei continue to absorb small oil droplets in the bulk phase to make the oil nuclei grow, so that the solubilization ability of the oil displacement agent system for crude oil is continuously enhanced, the oil and water are continuously mixed, and the interface between the nanosheets and the oil and water The "surface-surface" contact of the nanosheets increases the contact area of ​​the miscible front, enhances the interface properties, produces a lubricating effect on the flow of oil and water, and improves the flow capacity of crude oil; the dynamic adsorption effect of nanosheets can reduce the accumulation of surfactants and cosurfactants in rocks The amount of adsorption on the surface, thus reducing the cost.

Description

Technical field: [0001] The invention relates to the technical field of oil-displacement agents, in particular to a preparation method and application of a 2D nanosheet oil-displacement agent. Background technique: [0002] In my country's proven oil reserves, unconventional low-permeability reservoirs account for about 60% of the total reserves, but low-permeability reservoirs have small pore throats, complex pore structures, natural micro-fractures, and spatial scale distribution of fractures and pore throats. The range is wide, the fracture scale is at the micron level, and the pore throat scale is at the nanometer level. During water injection and gas injection development, the injection medium is prone to water channeling and gas channeling along the fracture channel, and the sweep efficiency is low; the traditional displacement medium cannot effectively enter the nano-scale pore throats to replace crude oil, and the oil washing efficiency is low. There are many kinds o...

AI Technical Summary

Problems solved by technology

During water injection and gas injection development, the injection medium is prone to water channeling and gas channeling along the fracture channel, and the sweep efficiency is low; the traditional displacement medium cannot effectively enter nano-scale pore throats to replace crude oil, and the oil washing efficiency is low

There are a variety of complex clays in the reservoir, which cause velocity sensitivity and water sensitivity in the process of conventional water injection development. The expanded clay minerals block the intergranular pores and cause serious damage to the reservoir.

The heterogeneity of the reservoir also has a great influence on the capillary force, resulting in the inhomogeneity of the displacement front, forming the phenomenon of flow around and blocking, resulting in the retention of a large amount of remaining oil

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