摘要 |
A process is disclosed for the recovery of heavy constituents from high-pressure hydrocarbon gaseous mixtures comprising the steps of first cooling and partially condensing the gaseous mixture. The condensed liquid is then separated and fed to a fractionation column while the remaining non-condensed gaseous mixture is subject to turboexpansion. The liquid condensed on turboexpansion is then separated and fed to the fractionation column where the heavy constituents are recovered. The gases streaming from the fractionation column and those separated by turboexpansion are compressed, separately or together, up to the consignment pressure of the treated gas. This process is characterized in that the liquid condensed on turboexpansion is separated in a separator-absorber wherein, in addition to the condensed liquid, a liquid obtained by the absorption of the non-condensed heavy constituents is collected. Absorption is accomplished by an absorbent hydrocarbon oil, substantially free from the heavy constituents to be recovered. This oil is obtained from the cooling and partial condensation of the gases streaming from the fractionation column wherein a portion of the heavy constituents are removed by means of a dephlegmator and substantially compressed to a pressure higher than the pressure of the fractionation column.
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