Multi-round polymer gel deep fine profile control method

Abstract

The multi-round polymer gel deep fine profile control method achieves the purpose of deep profile control by injecting slugs with different functions in multiple rounds. According to the role of slug in deep profile control, it can be divided into four types: first slug: gel diversion, providing preparation for the effective entry of gel into the formation; second slug: weak gel auxiliary plugging, effective connection and diversion agent and medium and strong gel to ensure that the fluid enters the formation effectively and continuously; the third slug: middle and deep plugging of the medium and strong gel; the fourth slug: active weak gel turbulence; Inject slugs I, II, and III as required, and reuse slugs II and III in the second (third) round. According to the pressure and working parameters, after the injection requirements are met, the next round of injection is performed; the last round of injection of the fourth slug. The slugging effect of multiple rounds of refined injection is more targeted and has a longer effective period, which can effectively improve the water absorption status of the reservoir, improve the utilization rate of injected water, expand the swept volume, and finally improve the oil displacement efficiency; the oil increase effect is obvious, and the method Simple and easy to implement, suitable for on-site implementation, especially suitable for wells with multi-layer mining, large interlayer differences, and high water content. The success rate of profile control can be increased to 90%, and the validity period can be increased by 1 or 2 years. It has a wide range of popularization and application prospect.

Description

technical field [0001] The present invention relates to the deployment stimulation measures in the drilling technology of IPC classification E21B soil layer or rock, especially the multi-round deep fine profile control method of polymer gel. Background technique [0002] Continental oil layers are the main oil layers in my country, and one block has multiple layers is one of its characteristics. Water injection development is the main development method of oilfields in my country. In the initial stage of oilfield development, the method of combined injection and production of all wells is generally used for production, that is, the development of a set of injection and production well patterns. In this development mode, due to the inherent heterogeneity of the oil layer itself, there will be interlayer conflicts, that is, interlayer interference, that is, due to the different permeability of the oil layers, when the whole well is flooded, the formation with high permeabilit...

AI Technical Summary

Problems solved by technology

However, due to the non-wetting properties of the profile control agent and the formation rock, it is difficult for the profile control agent to enter, and it is often forced to enter by increasing the pressure of the injection system.

In fact, most of the profile control agents are still stuck in the near-wellbore area, resulting in severe blockage in the near-wellbore area and empty pores in the deep reservoir, high water flooding pressure and low oil well energy