FIELD: gas industry.
SUBSTANCE: invention relates to equipment for production of low-pressure gas and liquefied hydrocarbon gases due to use of differential pressure between main and distributing pipelines of natural gas. Disclosed is an apparatus which includes a recuperative heat exchanger, a fractionating tower with upper and lower heat exchange sections, reducing devices, a fractionation unit, a heat exchanger and a separator. During operation of the plant, high-pressure gas is dried and separated into two streams, the first flow is fed into the lower heat exchange section of the column as the heat carrier, mixed with the second flow cooled in the heat exchanger, and directed to the middle part of the column, from the bottom of which the demethanized condensate is fed into a fractionation unit, from which hydrocarbon C2+ fractions are withdrawn in a given range, note here that part of low-pressure gas or part of de-ethanized gas is added to fractionator as cooling agent. De-ethanized gas coming from the top of the column is cooled in a heat exchanger, reduced and separated in a separator into LNG and low pressure gas, which is supplied as a cooling agent into a heat exchanger, an upper heat exchange section, a recuperative heat exchanger and discharged.
EFFECT: production of LNG, high output of hydrocarbons C2+ and elimination of use of external sources of low-temperature cold.
5 cl, 1 dwg
