Method And Device For Cryogenically Separating A Mixture of Hydrogen And Carbon Monoxide

A process for the cryogenic separation of a mixture of hydrogen and carbon monoxide for the production of pure CO, comprising

• cooling the mixture by partial condensation in an exchange line,
• introducing at least a portion of liquid resulting from the partial condensation into the top of a stripping column,
• withdrawing at least a first flow rich in carbon monoxide and a second flow rich in carbon monoxide from the stripping column in the liquid form and conveyed to the exchange line,
• expanding the first flow,
• conveying the expanded first flow to a separator pot, thereby producing a first vapor and a first liquid,
• reheating the first liquid in the exchange line,
• conveying the reheated first liquid to the first stage of a carbon monoxide compressor comprising at least two stages,
• expanding the second flow,
• reheating the expanded second flow in the exchange line,
• conveying the reheated expanded second flow to a stage of the compressor downstream of the first stage,
• reheating the first vapor and second flow in the exchange line at different pressures,
• expanding the first liquid and second flow to provide at least a portion of the separation energy of the cold box, and
• cooling the first liquid and second flow in the exchange line to different temperatures.

A device for the cryogenic separation of a mixture of hydrogen and carbon monoxide for the production of pure CO by partial condensation in a stage comprising

• an exchange line,
• a stripping column,
• a first and a second separator pot,
• a carbon monoxide compressor comprising at least two stages,
• means for conveying the mixture to be cooled into the exchange line,
• means for conveying the cooled mixture to the first separator pot,
• means for withdrawing at least a portion of the liquid resulting from the partial condensation from the first pot,
• means for conveying this liquid to the top of the stripping column,
• means for diverting at least a first flow rich in carbon monoxide and a second flow rich in carbon monoxide in liquid form from the stripping column,
• means for cooling the first and the second flows to a first and a second temperature respectively in the exchange line,
• means for conveying the first flow at the first temperature or the second flow at the second temperature to the second separator pot after expansion,
• means for reheating the gas from the separator pot in the exchange line,
• means for conveying the reheated gas to the first stage of the carbon monoxide compressor,
• means for expanding and for reheating the second flow or the first flow in the exchange line, and
• means for conveying the reheated second flow or the reheated first flow to a stage of the compressor downstream of the first stage, wherein the first and the second temperature are different.