Verfahren zum Auftrennen eines im wesentlichen aus Wasserstoff, Methan und C¶3¶/C¶4¶-Kohlenwasserstoffen bestehenden Einsatzstromes

摘要

A process for separating an intake flow consisting essentially of hydrogen, methane and C3/C4 hydrocarbons which has previously been subjected to a pretreatment, e.g. dehydration, after which the intake flow is taken through an at least single-stage partial condensation and separation into a C3/C4 hydrocarbon-rich fraction and an H2/CH4 fraction, whereafter a partial flow of the H2/CH4 fraction is mixed with the intake flow which has not yet been pretreated. The H2/CH4 gas fraction drawn from the first separator (S1) is divided into two partial flows (10, 17), the first partial flow (10) with the liquid fraction (W2) from the first separator (S1), after partial condensation (W2) being taken to a second separator (S2), the C3/C4 hydrocarbon-rich liquid fraction (16) drawn from the base of the second separator is taken with the second partial flow of the H2/CH4 gas fraction (17) from the first separator (S1) into a stripper column (S3), a highly pure H2-rich gas fraction (13) is drawn off from the head of the second separator (S2) and, after evaporation in heat exchanger (W2) against process flows to be cooled, is mixed with the intake flow (2, 2a, 2b) before its pretreatment, a C3/C4-rich product fraction (20) is drawn off from the base of the stripper column (S3) and a lower-purity H2-rich gas fraction (18) is drawn off from the head of the stripper column (S3).