摘要 |
An apparatus 150, for generating an oxygen enhanced gas by removing nitrogen gas from air, includes a compressor 156 absorption columns 152a and 152b for removing the nitrogen gas from the pressurized air supplied from the compressor 156, a flow rate measuring device 168 provided downstream of the absorption columns 152a and 152b, ultrasonic oxygen concentration measuring means 170 provided downstream of the flow rate measuring device 168. The ultrasonic oxygen concentration measuring means 170 includes means for generating a correction coefficient for the ratio between oxygen and argon gases contained in the oxygen enhanced gas on the basis of the flow rate of the oxygen enhanced gas measured. <IMAGE> |