Table 1. Oxygen specification for power generation system.
　 Power Generation System Output
[kW]		 Oxygen
flow rate
[Nm3/h]		 Pressure
[MPa]		 Purity
[%O2]
Case1 Monatomic Gas Circulation
type Hydrogen Diesel		 610 214 0.131 ≧ 97.0
Case2 Steam Circulation type Diesel 1044 532 0.592 ≧ 95.0
Case3 Solid Polymer Electrolyte
type Fuel Cell		 5000 1651 0.984 ≧ 96.0

Table 2. Comparison of specific power consumption of oxygen
　 Conventional Process Hydrogen Utilized
Single-column Double-column
Main Air Comp.
　Flow rate [Nm3/h]
　Outlet press. [MPa]
　Power [kW]
7960
0.58
657
8505
0.32
459
7970
0.33
445
Recycle Nitrogen Comp.
　Flow rate [Nm3/h]
　Outlet press. [MPa]
　Power [kW]

−
1703
0.58
54

−
Regenerating Heater
　Flow rate [Nm3/h]
　Power [kW]
1592
9
4763
31
4464
26
Total power [kW] 666 544 471
Oxygen Production
　Flow rate [Nm3/h]
　(100%O2 equiv.)
　pressure [MPa]
　purity [%]
1720
(1651)
0.127
96.0
1720
(1651)
0.137
96.0
1720
(1651)
0.137
96.0
Power consumption
[kWh/Nm3]		 0.403 0.330 0.286

Table 3. Comparison of specific power consumption
including oxygen compression power

　 Conventional Process Double-column Process Hydrogen Utilized
Main Air Comp.
　Flow rate [Nm3/h]
　Outlet press.[MPa]
　Power [kW]
7960
0.58
657
7970
0.34
455
Regenerating Heater
　Flow rate [Nm3/h]
　Power [kW]
1592
9
4464
24
Low Temp. Air Comp.
　Flow rate [Nm3/h]
　Outlet press. [MPa]
　Power [kW]
−
990
2.46
47
Oxygen Comp.
　Flow rate [Nm3/h]
　Outlet press.[MPa]
　Power[kW]
1720
1.08
240
−
Liquid Oxygen Pump
　Flow rate [Nm3/h]
　Outlet press. [MPa]
　Power [kW]
−
1720
1.10
1
Total power [kW] 906 527
Power consumption
[kWh/Nm3]		 0.552 0.319

Table 4. Rate of utilized hydrogen cold energy




　　Unit		 Range of hydrogen temp. [K] Rate of utilized hydrogen cold energy to the total supply

[%]		 Rate of utilized hydrogen cold energy for each unit

[%]
Nitrogen Condenser 23〜78 27.0 60.1
Sub-cooler 78〜94 4.5 10.0
Main Heat Exchanger 94〜137 13.4 29.9
Not utilized 137〜293 55.1 −
Total 　 100 100

Fig. 1. Conventional process

Fig. 2. Single-column process utilizing hydrogen

Fig. 3. Double-column process utilizing hydrogen

Fig. 4. Double-column process utilizing hydrogen
for producing high pressure oxygen