CHILLING SEPARATING METHOD AND DEVICE FOR CARBON MONOXIDE

PURPOSE: To separate and refine CO at a high yield in a simple apparatus by cooling a raw material gas, guiding liquefied CO and unliquefied gas in a rectifier, mixing the liquefied CO with hydrogen gas, performing evaporation and cooling the unliquefied gas. CONSTITUTION: A cooled raw material gas via a duct 42 is fed to a high pressure part 61 of a rectifier 6, and cooled by a condenser 63 and most of CO in the gas is liquefied. A gas remaining unliquefied becomes rich in H2 and introduced into a CO evaporator 9 via a duct 43. The liquefied CO is fed to this Co evaporator 9 to evaporate at the tube side and the high pressure H2 rich gas fed to the shell side is cooled and CO in the gas is further liquefied. The liq. CO is brought into contact with a CO gas contg. methane in a low pressure part 62 of the rectifier 6 to refine the gas to a high purity, and the refined gas and liq. CO contg. methane and discharged via the ducts 53, 54 respectively and both are heated in a main heat exchanger 3 and the former is discharged as a product CO gas.