FIELD: chemistry.
SUBSTANCE: invention relates to method of decomposition of nitrogen-containing initial fraction with high content of hydrocarbons, preferably of natural gas, including: partial liquefaction and separation by method of rectification of initial fraction into nitrogen-enriched and nitrogen-depleted fraction with high content of hydrocarbons. In upper rectification zone nitrogen-enriched flow is deviated, cooled and partially supplied to rectification as return product and/or nitrogen-enriched fraction is cooled and partially condensed, partially supplied to rectification as return product and residual flow of nitrogen-enriched fraction is subjected to process in two columns. In middle rectification zone flow with low content of carbon dioxide, used for cooling nitrogen-enriched partial flow and/or cooling nitrogen-enriched fraction, is deviated. Rectification of initial fraction is realised in separation column, provided with separating partition, with separating partition being located in the zone, where initial fraction is supplied into separation column and flow with low content of carbon dioxide is deviated.
EFFECT: invention makes it possible to do without extraction of carbon dioxide from initial fraction and natural gas flow, which is realised as washing with amine.
6 cl, 2 dwg
