| 摘要 |
The present invention relates to a process for processing a gas mixture comprising methane, carbon dioxide, carbon monoxide, hydrogen, nitrogen, argon and traces of olefins and oxygenates. Methane, carbon dioxide and carbon monoxide, and optionally hydrogen, can be recovered from the gas mixture in a very efficient way. |
| 主权项 |
1. A method for recovering hydrogen, methane and optionally carbon dioxide from a gas mixture comprising methane, carbon dioxide, carbon monoxide, hydrogen, nitrogen, argon and traces of olefins and oxygenates, said method comprising the following steps:
(1) feeding said gas mixture and an appropriate amount of steam through a high, medium or low temperature shift reactor(s) or a combination thereof to convert at least part of the carbon monoxide and water into hydrogen and carbon dioxide, to obtain an effluent; (2) Optionally, removing bulk water from the effluent obtained in step 1; (3) feeding the effluent of step (1) or (2) through a column comprising an adsorbent bed, wherein the adsorbent bed comprises alumina, a carbon molecular sieve, silicalite, activated carbon, a zeolite, or mixtures thereof,
with upon commencement of said feeding, the bed and column being pre-saturated and pre-pressurized to a pressure in the range of 10 to 80 bar absolute (bar a, anddischarging a second effluent from the other end of said bed, and;
continuing said feeding and said discharging until a front of carbon monoxide comprising gas has reached at least 45% of the length of the bed and has reached at most 80% of the length of the bed, preferably at most 70%, calculated from the end of the bed at which the effluent from step (1) and/or (2) is being fed; and (4) ceasing the feeding of the effluent from step (1) and/or (2) and reducing the pressure in the column and the bed by about 5 to 25 bar a; and (5) further reducing the pressure of the column and adsorbent bed to a pressure in the range of 5 to 25 bar a to obtain a fourth effluent; (6) further reducing the pressure of the column and adsorbent bed to a pressure in the range of 1 to 5 bar a; and (7) rinsing the column and adsorbent bed by feeding a mixture of hydrogen, nitrogen and/or argon through the column and adsorbent bed
the column and bed being at a pressure in the range of 1 to 5 bar a; and (8) pressurizing the column and adsorbent bed to a pressure in the range of 15 to 75 bar a. |
