| 摘要 |
<p>PURPOSE:To obtain high purity hydrogen gas by purifying hydrogen gas contg. impurity gas by a pressure swing adsorption method comprising specified five processes. CONSTITUTION:Three adsorption towers A,B,C, packed with an adsorbent such as zeolite or activated carbon are placed side by side as one unit. Valves 3a, 4a, 5a are closed, and raw gas consisting of hydrogen gas and one or more kinds of impurity gases is fed into tower A through pipe P1 and valve 1a to allow the impurity gases to be adsorbed. The purified hydrogen gas is recovered as product gas through valve 2a and pipe P2, and part of the gas is used to finish-purge tower B. Next valve 3a alone is opened to evacuate tower A and most of the impurity gases are exhausted through pipe P3. By opening valves 3a,4a pipe P4 and the outlet side of tower A are communicated to let raw gas flow into tower A countercurrently to purge the residual impurity gases in tower A. Valve 4a is then opened to commuincate pipe P5 and the outlet side of tower A, thereby coutercurrently introducing product gas from pipe P2 through pipe P5 and valve 4a to perform finish purge. Raw gas is introduced into tower A through pipe P1 and valve 5a and pressurized. The above processes are carried out in towers A,B,C in order.</p> |
