The current level and prospects for the development of large-volume injection technologies using polymers to increase oil recovery

Abstract

Currently, there is a worldwide decline in the level of production while maintaining the level of consumption. At the same time, the newly discovered fields are not able to compensate for the volumes of extracted oil, since the volumes of reserves are mainly small or medium. In this regard, it is relevant to introduce technologies to increase oil recovery at already drilled and developed fields. A promising method of increasing oil recovery is polymer flooding, which has many years of successful experience in both Russia and abroad. Polymer flooding technology consists in adding dry polymer to the injected water in concentrations from 0.05 to 0.25 % in order to increase its viscosity, which in turn contributes to improving the flooding process. The polymer rim equalizes the ratio of mobility in the reservoir and allows oil to be uniformly displaced from reservoirs in which there is a heterogeneity in permeability. The key result in the implementation of the technology is an increase in the oil recovery coefficient by improving the coverage of the reservoir by the flooding process, as well as a gradual increase in water availability, without early water breakthroughs from injection to production wells. This technology has wide limits of applicability and has already proven its effectiveness in various geological and physical conditions. This article will consider the physical basis of exposure, the principle of action, the criteria of applicability, the main groups of chemical reagents, and the accumulated domestic and international experience in the design and implementation of polymer flooding technology, development trends and the main difficulties associated with the introduction of this technology.