PROCESS AND APPARATUS FOR THE SEPARATION OF CARBON DIOXIDE AND HYDROGEN

摘要

A separation process and apparatus, wherein carbon dioxide (CO2) is separated from a gaseous feed stream comprising CO2 and hydrogen (H2), and comprises the steps of: (i) cooling and partially condensing the feed stream; (ii) passing the cooled and partially condensed feed stream from step (i) to a first vapour-liquid separator to produce a vapour stream having increased H2 content relative the feed stream and a liquid stream having increased CO2 content relative to the feed stream; (iii) expanding at least a portion of the liquid stream from step (ii); (iv) passing the expanded stream from step (iii) to a second vapour-liquid separator to produce a vapour stream having increased H2 content relative the liquid stream from step (ii) and a liquid stream having increased CO2 content relative to the liquid stream from step (ii); (v) expanding and heating a first portion of the liquid stream from step (iv); wherein cooling in step (i) is provided at least in part by heat exchange during heating of the first portion of the liquid stream from step (iv) in step (v).  Advantageously the separation process uses heat integration techniques to improve the efficiency of the process and to minimise the power requirements for downstream compression.