Analysis of the directions for improving the development systems for oil fields at the later stage

Abstract

The object of research is oil fields at a late stage of their development. The most problematic issues in the development of oil fields are the formation and withdrawal of residual oil reserves. This problem is especially acute at the late or final stage, when the oil productivity of the wells decreases and the water cut of the production catastrophically increases. The most acceptable development system in such conditions is the use of methods for increasing oil recovery and, first of all, by injecting water into the reservoir. At the same time, the problematic issue is the lack of reliable information on the paths of water movement from injection to production wells and the imperfection of methods for aligning the injectivity profile in injection wells and the flow profile in production wells.

In the course of the study, statistically analytical methods were used to analyze the state of development of oil fields at a late stage and industrial approbation of methods for tracing water movement and substantiation of a reagent base to align the paths of water movement and oil inflow.

A set of reagents and technological methods for ensuring the regulation of the process of flooding of oil fields at a late stage of their development have been investigated and developed. It has been proven that a promising direction is the injection of a 0.1 % aqueous solution of the Polycar polymer together with water. This solution first of all penetrates into highly permeable, water-washed, formation intervals, contributing to the leveling of the injectivity profile, reducing the water cut of surrounding production wells and increasing their oil productivity.

Thanks to the research carried out, directions and means of improving the systems of field development at a later stage have been developed by organizing targeted (selective) waterflooding of oil deposits based on high-quality and comprehensive control of the movement of filtration flows in the reservoir. This will ultimately contribute to achieving and maintaining the design value of reservoir pressure, preventing a decrease in the rate of decline in oil production, obtaining the design value of the sweep efficiency by waterflooding, and withdrawing residual oil reserves.