| 摘要 |
Air is separated in a vessel 14 housing gas separation membranes. A flow control valve 10 controls the passage of air to an inlet header 12 of the vessel 14. The setting of the valve 10 is adjusted in accordance with the level of oxygen impurity in product nitrogen leaving the vessel 14 for an outlet header 16. A second flow control valve 30 is provided and is of a kind whereby product nitrogen is able to be delivered at a constant flow rate over a range of different pressures upstream thereof. Accordingly, the apparatus is able to deliver nitrogen at a desired purity and flow rate. |
