Combined method of impact on layered-heterogeneousn formation based on in-situ steam generation

Abstract

This article discusses the combined method of influencing a layered-heterogeneous reservoir. In-situ steam generation (IPSG) is used as the main method, which in turn can be considered a combined technology of hot water injection and in-situ combustion. In order to improve the efficiency of the IPSG, it is proposed to inject a slug of an alkali solution (NaOH). The main mechanism in the application of IPSG is thermal interference between layers of different permeability. The use of alkali allows us to use its positive properties. The use of alkali allows us to use its positive properties. Such as lowering the surface tension at the boundary of the oil solution of alkali, the formation of an emulsion. The formation of an emulsion in a high-permeability layer contributed to an increase in the pressure drop in it and, accordingly, changed the direction of the fluid flow. Most of the injected water-air mixture began to flow into the low-permeability layer. Thus, the effectiveness of the impact on the formation was increased. The effect of alkali solution concentration on oil displacement from a layered-heterogeneous reservoir is estimated. The proposed technology made it possible to increase the coverage of the layered formation by the process and, accordingly, increase the oil recovery factor. Experiments were carried out for two oils with different viscosities: 86 mPa.s and 510 mPa.s.