摘要 |
<p>The aim is to separate, by cooling and partial condensation of C2+, C3+ or C4 hydrocarbons contained in a gas mixture comprising, in addition to these components, even lighter constituents. For this purpose, the gas mixture is at first cooled until condensation of a smaller part of the hydrocarbons to be separated, after which the mixture is fed into the lower region of a fractionating column. A gaseous fraction is removed from the upper region of said column and is then again cooled and partly condensed in a heat exchanger, after which this partly condensed fraction is conveyed to the top of the fractionating column in the form of a return flow. In the case of C4 separation, the C4 hydrocarbons must represent more than 50% of the hydrocarbons contained in the gas.</p> |