GAS SEPARATION APPARATUS

PROBLEM TO BE SOLVED: To produce, a separated gas at pressure as high as at least withstand pressure of a gas separation apparatus, which produces a separated gas of a desired gas component from a gas mixture containing multiple components, by installing a separator main body provided with gas separation membranes and a pressure resistant container having pressure resistant property equal to or higher than that of the separator main body. SOLUTION: During the time of operation of this separation apparatus, the air supplying pressure value by a compressor 5 is calculated by a control apparatus based on the nitrogen gas producing pressure value and based on the supplying pressure value and the withstand pressure value of the separator main body 7, the container pressure value of a pressure resistant container 6. Based on the pressure value of the container, a pressure adjusting valve 24 is set and based on the supplying pressure value and the container pressure value, a differential pressure control valve 26 is set. In such a condition, the compressor 5 is driven and the differential pressure control valve 26 is so controlled as to keep the differential pressure between the inner pressure of a raw material gas chamber 21a and the inner pressure of the pressure resistant container 6 at a prescribed value or lower. The air supplied to the separator main body 7 is led to hollow yarns 23 and unnecessary gas components in air are removed.