METHOD OF LIQUEFACTION OF NATURAL GAS THROUGH CYCLE OF PARTIAL LIQUEFACTION DUE TO CHANGE IN PRESSURE AND INSTALLATION FOR ITS IMPLEMENTATION Russian patent published in 2019 - IPC F25J1/00 

FIELD: technological processes; gas industry.

SUBSTANCE: invention relates to the gas processing industry and can be used to liquefy natural gas at gas distribution stations (GDS). Gas taken before GDS 14 is dried in the drying unit 1 and divided into production and process flows. Process stream is compressed in compressor 4 of the turbo-expander unit (TEU), cooled in heat exchangers 6 and 7 and sent to expander 5 TEU and then to recuperative heat exchangers 9, 7 and 6 to cool the process and production gas flows, and then direct it to the output of GDS 14. Production flow is cleared of CO₂ in block 2 of cleaning. Part of the gas of the production flow after cleaning is directed through pipeline 3 to the process stream before it is compressed in compressor 4. Rest of the production stream is cooled sequentially in heat exchanger 7 by the process stream and in cryogenic heat exchanger 9 by the evaporation gas from end separator 10, they are throttled and the resulting vapor-liquid mixture is sent to end separator 10, from which liquefied gas is directed to storage tanks 11.

EFFECT: invention reduces the sensitivity of the installation to CO₂ and increase its productivity by reducing the content of CO₂ in the process stream.

6 cl, 1 dwg