| 摘要 |
<p>Pure gaseous hydrogen and liquid carbon dioxide are produced by reacting hydrocarbon in a stream reformer 14 and a shift convertor 28 and passing the effluent from the latter through a four bed hydrogen PSA separator unit 38 and then a carbon dioxide PSA separator unit 48. The carbon dioxide PSA unit 48 produces a hydrogen-rich stream which is recycled to the feed to the steam reformer 14, a carbon dioxide-rich recycle stream which is recycled to the feed to the carbon dioxide PSA unit 48 and a carbon dioxide-rich product stream which is compressed in compressors 62 and 64, partially condensed in heat exchanger 68 and separated in a distillation column 70 to produce a pure liquid CO2 product. A waste stream from the column 70 is recycled to the feed to the carbon dioxide PSA unit 48. A portion of the carbon dioxide-rich product stream is withdrawn intermediate the compressors 62 and 64 such that its pressure is higher than the operating pressure of the carbon dioxide PSA unit 48 and returned thereto as a cocurrent purge preceding bed regeneration to obtain the carbon dioxide-rich product stream.</p> |
