| OCR Text |
Show * Fig. 15 tells the following matter. In 100 $/m2 of the membrane cost, the price of oxygen enriched air (02 = 26%) is found to be 1.44 <£. on condition of 8,000-hour operation and thus equivalent to 17.1 tfVkg in the price of liquified oxygen. Therefore, when annual operation hours are small, it can be said that the membrane still more highly costs. However, reduction of the membrane cost to 50 $/m2 brings equivalence to 12.3 0/kg in the price of liquified oxygen and much reduction of the membrane cost to 25$/m2 can provide equivalence to 10.1 ?Vkg in the price of liquified oxygen. the Fig. 16 shows the comparison between the price of liquified oxygen and that of oxygen enriched air when the fective measures to save energy as described above. The description so far refers to the cost-cutting of membrane with the membrane capacity kept constant. On the contrary, even if the cost per unit area of membrane remains constant, improved capacity of membrane allows the system to become an effective measure for saving energy. Based on the same conditions as those of Fig. 15, the Fig. 16 shows the comparison between the price of liquified air and that of oxygen enriched air when the improved capacity of membrane brings the oxygen concentration of 28% and 30% on condition of 100 $/m2 in the membrane cost. j -23 - |
