PURIFICATION OF LIQUEFIED NATURAL GAS Russian patent published in 2010 - IPC F25J3/02 

FIELD: technological processes.

SUBSTANCE: method for purification of liquefied natural gas (1) for production of liquid flow (21) having lower content of components with lower boiling points includes expansion of liquefied gas for production of expanded double-phase flow. Double-phase fluid medium is introduced into column (10') below section (14') of gas and liquid contact. From lower part (16) of column flow of liquid (17') is drained with lower content of components with low boiling points. Flow of liquid is introduced into evaporation chamber (101). From upper part (23) of column gaseous flow (25) is drained from column (10'), rich in components with low boiling points. Gaseous flow is heated in heat exchanger (27). Gaseous flow is compressed till pressure of fuel gas to produce fuel gas (33). Separation of recirculating flow (34a) from fuel gas; at least partial condensation (27) of recirculating flow to produce reflux flow (34b); introduction of reflux flow (34b) into column (10') over section (14) of contact.

EFFECT: application of invention makes it possible to simplify technological process and reduces content of low boiling components in flow of liquid product.

21 cl, 6 dwg, 1 tbl