This paper describes main processes used for removal of CO 2 from natural gases and some results of under R&D technologies of acid gases extraction from natural gases, including the method of 3S-technology (SuperSonic Separation technology).There are various methods of acid components extraction from the natural gas: adsorptive, adsorptive, membrane, cryogenic and their various combinations. All mentioned technologies are notable for necessity to use a large number of accessory equipment, including bulky one that leads to the high capital investment costs and great operational costs, and also to the costs for restoration of adsorbents/absorbents, clearing of membranes, etc. These circumstances make the existing technologies inapplicable in terms of cost efficiency.At the same time, a significant progress was recently being made in the development of new low-temperature processes of extracting CO 2 from natural gas. Low-temperature processes are specially promising in processing of gases with high CO 2 content. Several low-temperature processes of CO 2 removal are presently known: -Ryan Holmes method; -Controlled freeze zone method (CFZ); -Cryocell method (Cryocell); -Sprex method (Sprex); -Gasdynamic separation of gas mixtures (3S-separation).All 5 above mentioned low-temperature processes of acid components extraction will be considered and analysed in this paper.While the main focus is on the analysis of 3S-separation technology. 3S-separator is a low-temperature supersonic separator, based on natural gas cooling in a supersonic swirling flow. Supersonic flow is implemented using a convergent-divergent Laval nozzle. In this nozzle, rapid cooling of gas takes place due to the conversion of flow potential energy into kinetic energy.This workcontains a detailed description of 3S-technology. Someexistential schematic diagrams of devises based on 3S-separation will be presented in this paper. The advantages and limitations of this technologyhave been investigated during the study.Currently3S-separators have been successfully operatedat severalgas processing facilities. Experimental studiesof CO 2 separation from naturalgaswere carried out onthe test unitwith the3S-separator, designed for 6000 nm 3 /hour gas flow. Duringtests it has been shownthat the technologymakes possible theseparation of CO 2 inthe carbon dioxide crystallization zone. The performed tests demonstrated that it is possible to achieve less than 3% mol CO 2 concentration in the inlet gas.