| 摘要 |
<p>PURPOSE:To improve purity of a product gas, by equipping gas supplying valves, exhausting valves, product gas drawing out valves, and a purging valve in an adsorbing tower; opening the purging valve when the pressure of the tower decreases to near normal pressure; and purging the tower with the part of the product gas. CONSTITUTION:An adsorbing tower 1 is in exhausting process by opening an air supplying valve 7 and an air exhausting valve 11 and feeding air to an adsorbing tower 2 to elevate the pressure. Then, product N2 gas is introduced into a product tank 18 from the tower 2 through an drawing out valve 17. When the inner pressure of the tower 1 becomes near atm pressure as its evacuation is proceeding, a pressure sensor 1B detects that and a purge valve 23 and a pressure-uniformalizing purge valve 26 are opened by an order from a controlling apparatus 28 so as to feed the part of product gas for purging and remove remaining oxygen. At last, the recovering the part of compressed air to the adsorbing tower 1 from the tower 2, gas yield is improved.</p> |
