Page 297 - Pressure Swing Adsorption

'
ii.,
274 PRESSURE SWING ADSORPTION EXTENSIONS OF THE PSA CONCEPT 275

Figures 7.6-7.8. Even with a modest pressure ratio 1t 1s possible to recovery
essentially oure hydrogen at fractional recoveries greater than 95% from a
feed contammg 74% H together with CO and CO (Figure 7.6). Similariy,
2
2
for air separation (Figure 7.7), essentially complete elimmalion of mtrogen to
produce a product contammg about 95% 0 + 4.5% Ar can be easily
2
accomplished, with a moderate pressure. ratio, at a fractional recovery of
about 67%. Even at comparatively iow cycle speeds the oroduct1v1ty (Figure
7.8) 1s seen to be far supenor to that of convent10nal PSA systems.
◊
CJ

% H2

99

94
D

+ 1000 ccimln.
89
... D 200 ccfaain •
a
l\'
~ 0
" !
0
"" 84 Conditions:
u 10 rpm
0 0
-g HPF ~~
"
"' L-AB
2P
79
r
~
1'
fil
T D X ◊ <J
74 L.___J _ _L_._L.._~__J--L_._L.._~__J--L_J__~__J--+
30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 I
Flow Split % 1--.-r--,--,--,-i---r-,----,--.-,----j_ .,
0 w w .,
a "' "' 0 m "' a
Figure 7.6 Performance of a TCPSA unit m the separation of svnthes1s ga~ (74% "' "' m "' "'
Hz, 25% CO:?• 1% CO). The hydrogen product purity 1s plotted agatnst the flow split "' "' "' "' "' "
(i.e., the fraction or feed withdrawn as light product). Adsorbent 13X zeolitc ~ 350
3
cm bed volume. Operating pressure 2.4 atm-i atm, IO rpm. Feed 200 cm~/mm, D;
WOO cm·;/mm, +. The theoretical line is calculated from the mass balance for 100% Czo :.:J .ut<1nd .wna□<1d
pure product. (Courtesy of Highqucst Engmecnng, Inc.)