Analysis and optimization of liquification of natural gas under the conditions of a gas distribution station

Theoretical aspects of natural gas liquefaction at a high-pressure gas distribution station using the Claude open cycle are considered. Based on the thermodynamic analysis of the cycle, it is shown that there are two modes of gas liquefaction: if the initial gas pressure is higher than the critical one, the liquefaction process by throttling the production flow can be considered as isenthalpic; if the initial gas pressure is below the critical one, the process of gas throttling and liquefaction should be considered as a set of processes of isentropic expansion and subsequent adiabatic expansion and deceleration of the production flow. For both modes, mathematical models and algorithms for numerical calculation of the natural gas liquefaction process have been developed. The value of the maximum yield of liquefied gas was estimated, taking into account its real properties and existing restrictions. It is shown that the obtained calculation results are in good agreement with the known experimental data.