Multifunctional nano-viscosity reduction profile control agent

Abstract

The invention provides a multifunctional nano-viscosity reduction profile control agent, relating to an additive for thick oil exploitation in the chemical field of oil exploitation and a use method thereof. The agent disperses the continuous thick oil to an oil-in-water oil block by a low interfacial tension mechanism, and has the characteristics of high viscosity reduction rate, dispersed system while flowing, layering while being still, no influence on emulsion breaking, small use concentration and great economical feasibility. The technique combines the viscosity reduction, the profile control with displacement of reservoir oil, which can not only reduce the viscosity of the thick oil and regulate a water absorption profile, but also improve the efficiency of the displacement of reservoir oil, therefore, the integration of displacement and control is realized so that the technique is an organic combination of secondary oil recovery and tertiary oil recovery as well as has remarkable comprehensive economic benefit. By adding an assistant agent of a foaming agent, the method increases fluid film strength, prolongs foaming half life period, enhances foaming stability and sufficiently solves the problems of high viscosity of the thick oil and difficult development in the process of oilfield development and exploitation; the characteristics of nano-particles are utilized to exert cooperative effect between the agents to the maximum extent so as to realize the objective of viscosity reduction, profile control and efficiency increase.

Description

technical field [0001] The invention belongs to the field of petroleum exploitation chemistry, and in particular relates to a viscosity-reducing profile-controlling agent used in the heavy oil exploitation process and its application method. technical background [0002] Steam injection thermal oil recovery is one of the most extensive and most profitable methods for developing heavy oil reservoirs. However, with the increase of the throughput cycle, the cycle oil production rate gradually decreases, the water content of the produced fluid increases, and the production effect becomes increasingly poor. The reasons for the poor production effect after multiple rounds of huff and puff of thermal recovery with steam injection are due to low steam sweep efficiency and low displacement efficiency. Foaming agent as steam mobility profile control agent and oil-water selective plugging agent can effectively solve the above problems. Because the foam can not only increase the fluid...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is: in order to overcome the disadvantages of poor high-temperature foam stability generally existing in existing foam agents, unsatisfactory water solubility and salt resistance, small viscosity reduction range and short cycle, anionic surfactants and nonionic The compounding of surfactants improves its temperature resistance and salt resistance, the addition of viscosity-increasing foam stabilizers improves foam stability, and the addition of alkaline additives and nanomaterials produces synergistic effects with the foam system to improve the viscosity reduction of the foam system The effect of profile control