Waterflooding, water-gas method and generation of carbon dioxide in the reservoir – methods of enhanced oil recovery and technology development

This article discusses reservoir pressure maintenance methods: flooding and SWAG technology. The accumulated experience of waterflooding technology introduction described in literature sources is analyzed. Identified such disadvantages of waterflooding as reservoir watering due to significantly low viscosity compared to the viscosity of reservoir oils and low oil recovery factor. A method for detecting and preventing the instability of the front of displacement of residual reserves by injected water is indicated. Particular attention is paid to the innovative method of reservoir stimulation, which consists in the generation of carbon dioxide in reservoir conditions. The essence of the technology, method of implementation, advantages compared to gas injection through injection wells are described. Water-gas methods are investigated. The advantage of SWAG technology with the use of pump-ejector systems in comparison with other modifications is proved and the results of the latest research are presented, which cover data on the characteristics of pump-ejector systems, the topical issue of the technology for obtaining water-gas mixtures and the processes of interaction of gas bubbles when pumping mixtures through wells into the reservoir, as well as ways to implement the technology, taking into account the geological and field conditions of potential targets for implementation. This analysis will allow you to correctly choose the method of stimulation of the reservoir and operate the facilities as efficiently as possible. It should be noted that the considered gas and water-gas methods involve the injection of carbon dioxide, associated, exhaust, flue gases into the reservoir, which makes these technologies the most attractive from an environmental point of view.