PROCESS AND APPARATUS FOR RECOVERING C2+ OR C3+ HYDROCARBONS

摘要

Sepn. of 2C+ or 3C+ hydrocarbons from a gas stream contg. light hydrocarbons and possibly components lower-boiling than CH4 includes (i) partial condensation of the high pressure mixt. and sepn. into a liq. and a gas fraction and (ii) sepn. of the liq. fraction in a rectifying column (I) into a prod. stream contg. 2C+ or 3C+ hydrocarbons, and a residual gas stream largely contg. lighter components; and, as the improvement, (iii) feeding the gas fraction from step (i) to a backwash column (II) in which 2C+ or 3C+ hydrocarbons are washed out of it by the residual gas stream from step (ii) after its partial condensation, and the liq. fraction collecting in the bottom of the column is sent for rectification.