초록 ▼

An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon. The method includes

An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon. The method includes producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. An aircraft fuel tank flammability reduction system includes a source for pressurized air, an air separation module configured to receive air feed from the pressurized air source, and a carbon membrane containing at least 95 weight percent carbon. The carbon membrane is configured to permeate oxygen from the air feed through the carbon membrane at a temperature of at least 120° C. (248° F.) and to produce nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed.

대표청구항 ▼

1. An aircraft fuel tank flammability reduction method comprising: feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon;contacting the

1. An aircraft fuel tank flammability reduction method comprising: feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon;contacting the carbon membrane with the air feed, permeating oxygen from the air feed through the carbon membrane, and producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed; andfeeding the nitrogen-enriched air into the fuel tank on board the aircraft. 2. The method of claim 1 wherein the carbon membrane comprises a carbon hollow fiber, a spiral wound carbon fiber sheet, a carbon nanotube sheet, or combinations thereof. 3. The method of claim 1 wherein the carbon membrane comprises a pyrolyzed polymer hollow fiber. 4. An aircraft fuel tank flammability reduction method comprising: feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and a temperature of at least 120° C. (248° F.), the carbon membrane containing at least 95 weight percent carbon;contacting the carbon membrane with the air feed, permeating oxygen from the air feed through the carbon membrane, and producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed; andfeeding the nitrogen-enriched air into the fuel tank on board the aircraft. 5. The method of claim 1 wherein the air feed exhibits a temperature from 120° C. to 195° C. (248° F. to 383° F.). 6. The method of claim 1 further comprising feeding the pressurized air from a source for the pressurized air into the air separation module without substantially cooling the air feed in a heat exchanger. 7. The method of claim 4 further comprising substantially cooling the nitrogen-enriched air in a heat exchanger before feeding the nitrogen-enriched air from the air separation module into the fuel tank. 8. An aircraft fuel tank flammability reduction method comprising: feeding pressurized air into an air separation module containing a pyrolyzed polymer hollow fiber, the air feed exhibiting a temperature from 120° C. to 195° C. (248° F. to 383° F.), the hollow fiber containing at least 95 weight percent carbon, and the hollow fiber exhibiting a selectivity ratio of oxygen permeability to nitrogen permeability of at least 9 and a permeance of at least 80 gas permeation units when measured at an operating temperature of 160° F.;contacting the hollow fiber with the air feed, permeating oxygen from the air feed through the hollow fiber, and producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed;substantially cooling the nitrogen-enriched air from the air separation module in a heat exchanger; andfeeding the cooled nitrogen-enriched air into the fuel tank on board the aircraft. 9. The method of claim 8 wherein the air feed exhibits a normal pressure of no more than 55 psig.