This master thesis presents an analysis of current situation in Russian natural gas industry and analyzes different ways of gas primary treatment, such as compression method, absorption and adsorption cleanings, and finally, low-temperature separation (LTS). Among all existing techniques, LTS technology is one of the most common and effective methods of drying crude natural gas in the North fields. In LTS technology, separation process is preceded by a cooling process using traditional cold-producing devices (throttle, ejector and turbo-expander) due to the Joule-Thomson effect or an external cooling cycle. The main purpose of this study was to prove the possibility of using a vortex tube in LTS technology, as a result of which it is assumed to increase the degree of heavy hydrocarbons extraction such as C3+ and C5+. To check the adequacy of the proposed technology, its computational model was created in Aspen HYSYS software package and mathematical calculation of geometric and thermodynamic parameters of vortex tube was performed. After calculating the economic efficiency of this technology and comparing it with traditional LTS installations, it is established that LTS technology with vortex tube application is economically profitable.