Process for producing carbon monoxide gas.

摘要

A process for producing CO gas without using expensive conventional apparatus, in a simple manner in a high purity and with energy saving is provided, which process comprises a step of introducing a by-produced gas such as a mixed gas obtained by reforming or partially oxidizing hydrocarbons, steel converter gas, etc. into a pressure swing adsorption cycle (PSA) system; an adsorption step or adsorbing CO2, methane, CO, N2, H2, etc. in an adsorption column of the PSA system to obtain a H2-rich gas or a N2-rich gas passed; a step of depressurizing the adsorption column in the cocurrent direction to obtain a CO-rich gas discharged; a step of depressurizing the adsorption column direction in the counter current direction just prior to start of substantial desorption of methane and CO2 to obtain a CO2-rich gas discharged therefrom and having CO2 and methane concentrated therein; and a step of repressurizing the adsorption column using a H2-rich gas or a N2-rich gas obtained at the beginning of the adsorption step and the depressurizing step in the cocurrent direction.