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The proposed solution relates to fluidics and can be used, for example, in the extraction of oil and gas, the collection and preparation of oil, gas and water, the extraction of methane from methane beds, oil refining. The technical result is to increase the efficiency of a liquid-gas ejector by ensuring its work in the field of rational concentrations and salt composition, in which the intensification of energy exchange between the working fluid and the ejected gas is achieved. The essence of the proposed solution: the method of operation of a liquid-gas ejector involves injecting a working fluid with a power pump into the ejector nozzle, pumping gas with an ejector, creating, dispersing and increasing the pressure of a gas-liquid mixture with an ejector using aqueous solutions of salts as a working fluid. The values of the concentration and composition of salts in the working fluid are maintained within the range of rational concentrations and composition of salts, in which increased values of the efficiency of the ejector are achieved. Salts are added to the weakly mineralized aqueous solutions, and the highly mineralized aqueous solutions are diluted with fresh water. As the working fluid, the formation and/or incidentally produced waters of oil, gas, gas condensate and methane-coal deposits, which are aqueous solutions of salts, are used if the composition and concentration of salts in the produced and/or incidentally produced waters are within the range of rational concentrations and composition of salts in which provides an increase in the efficiency of the ejector. The boundaries of the field of rational concentrations and salt composition are preliminarily determined by laboratory bench studies.

At present, it is becoming more relevant to use other displacing agents, which are more effective in comparison with waterflooding, for increasing oil and gas condensate deposits component recovery. One of such promising methods is simultaneous water and gas injection. In this article, we present the principal options for using simultaneous water and gas injection in Arctic fields, case study of the Urengoyskoye and Prirazlomnoye fields. Technological schemes for its implementation in the Urengoyskoye field at low reservoir pressures are considered. Filtration studies of oil from reservoir models with water-gas mixtures at various gas contents allow increasing hydrocarbon recovery efficiency by determining the area of rational gas contents. For the conditions of the Prirazlomnoye field, the possibility of using pump-ejector system for the utilization of associated petroleum gas has been established.

The amount of unconventional oil resources in the world is increasing more and more up today, therefore the search for effective methods of layer stimulation is required. One of the methods of Enhanced Oil Recovery (EOR) is water-gas injection with a new approach - simultaneous injection of water and gas (SWAG - Simultaneous Water Alternating Gas) as a mixture with a bubble structure by means of multistage pump-ejecting systems. They allow to prepare a stable water-gas mixture on the surface and to inject it into the reservoir, using simple, reliable, and commonly used equipment. The main effects of SWAG are enhanced oil recovery and utilization of low-pressure associated gas. Distinctive features of the pump-ejecting technology are a minimum of capital investment and the use of existing oil-field infrastructure. For the conditions of Russkoye and Samodurovskoye oil fields laboratory filtration tests on sand-packed models were conducted, and also calculations of different process flowsheets based on the results of ejectors and ESP bench tests were carried out. Experiments have shown that SWAG significantly increases the oil-displacement efficiency, while the maximum effect is observed in the gas content 25% with the addition of surfactants in a water-gas mixture. Selected technical layouts of pump-ejecting systems allow injecting the water-gas mixture under a pressure up to 16 MPa at the lowest inlet pressures. Due to developed technical solutions the used equipment can operate in wide ranges of adjustment without significant reduction in the energy efficiency. Thus, the generalized results have showed high efficiency and availability of this technology at a number of Russian oil fields.

"Simultaneous water and gas" (SWAG) injection is the effective method of enhanced oil recovery. However, until recently the effect of SWAG in the development of heavy oil fields has been studied insufficiently. In the present study laboratory researches have confirmed that SWAG injection when 25% gas content in the mixture significantly increases the displacement efficiency of heavy oil with the viscosity 217 mPa*s of Russkoye deposit, compared with water flooding. It has allowed extending the effective application of SWAG as a non-thermal method of enhanced oil recovery more than twice. According to the results of laboratory experiments to pre-extracted and not extracted core material, it was found that the degree of hydrophobic pore surface, which depends on the adsorption of polar components of oil, significantly affect the oil displacement efficiency when SWAG implementing. It was established that SWAG at the optimum gas content is effective for both hydrophilic and hydrophobic environments. The values of the heavy oil displacement efficiency for the hydrophilic core material of Russkoye field are about 1.8 times higher than for hydrophobic. The technology for SWAG injection from the use of mono-block multistage pump-ejecting systems has been developed. The technology can significantly improve the systems efficiency and the process of water-gas mixtures delivering into injection wells. The obtained results allow creating non-thermal energy-efficient methods for developing and improving oil recovery of heavy oil fields.