| 摘要 |
<p>PURPOSE:To produce gaseous N2 having high purity at high efficiency by introducing O2-contg. gas consisting primarily of N2 into an adsorption tower packed with synthetic zeolite, allowing the gas to contact with the packed material for a specified time, then evacuating the tower after adsorbing N2. CONSTITUTION:Feed gas consisting primarily of N2 and contg. O2 is compressed with a compressor 1 in a pressure swing adsorption apparatus and fed to a pretreating tower 21a of 21b. After removing H2O, CO2, etc., by adsorption, the gas is introduced through a pressure adjusting tank 22 into one of packing towers 3a-3c, for example 3a, packed with synthetic zeolite, in which >=95% of the synthetic zeolite has 7-10Angstrom pores size. The gas is, thus, allowed to contact with the packed material under such condition that the mean contact time T(sec) expressed by T=L/V is <=30sec [where L is the length(m) of the adsorbent layer; V is the mean superficial velocity in the tower (m/sec)] to adsorb thus N2. Thereafter, a part of produced N2 having high purity is introduced into the tower 3a as washing gas to replace and remove remaining O2, then N2 having >=99.9% purity is desorbed and recovered by reducing the pressure in the tower 3a to, for example, ca. 100Torr by a vacuum pump 6, and produced gas is stored in a produced gas tank 9, and discharged at need through discharge pipe 2.</p> |
