Liquid-gas ejectors (LGE) are widely used for the disposal of low-pressure gas, pumping and compression of associated gas in oilfield systems used for gathering, processing and transport of wellbore fluids. Despite their advantages, such as simple design, reliable performance and low cost, a significant drawback of liquid-gas ejectors until recently was relatively low efficiency, slightly over 20%.
As a result of research conducted in the Ivano-Frankivsk National Technical Oil and Gas University under the direction of K.G. Donets (Doctor of Engineering), standardized LGE with 4 types of aerodynamic configuration and efficiency up to 40% were developed. The research identified that, in addition to the optimal, there are two other boundary modes of LGE operation: stalling and critical.
Formally, LGE with all four types of aerodynamic configuration can be used in pumping and ejecting plants used for compression of associated gas. However, they have different performance characteristics, which must be taken into consideration. The type of aerodynamic configuration of the liquid-gas ejector used in pumping and ejecting plants is determined based on the characteristic representing the dependence of mixture pressure from the pumped gas flow rate. This characteristic is not universal, because it must be developed for each specified pumped gas flow rate, it does not contain information on other operating parameters of the liquid-gas ejector: compression of the gas mixture, wattage, efficiency. In this paper, the authors developed a universal dimensionless characteristic for fluids and gas ejectors that does not depend on the flow rate of pumped gas and the characteristic of the used pump, which allows you to immediately choose the most preferred type of aerodynamic ejector scheme.
