On-board aircraft reactive inerting dried gas system

Patent metadata

Field	Value
Publication number	US-10150571-B2
Application number	US-201615348287-A
Country	US
Kind code	B2
Filing date	Nov 10, 2016
Priority date	Nov 10, 2016
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

An on-board aircraft inert gas system includes a source of hydrocarbon, a source of gas comprising oxygen, and a first fluid flow path between the source of gas comprising oxygen and an inert gas output. A reactor is disposed along the first fluid flow path that reacts oxygen and hydrocarbon from the fuel tank gas space to produce an oxygen-depleted gas. A heat exchanger condenser removes some water from the oxygen-depleted gas. A water-permeable gas membrane separator receives the oxygen-depleted gas from the heat exchanger and outputs dried oxygen-depleted gas.

First claim

The invention claimed is:

1. An on-board aircraft inert gas system, comprising:
a source of hydrocarbon;
a source of a gas comprising oxygen;
a first fluid flow path between the source of gas comprising oxygen and an inert gas output;
a reactor disposed along the first fluid flow path comprising an inlet that receives hydrocarbon and the gas comprising oxygen and reacts the hydrocarbon with the oxygen to produce an oxygen-depleted gas comprising water vapor, and an outlet that outputs the oxygen-depleted gas comprising water vapor;
a first heat exchanger comprising a water-condensing heat rejection side disposed along the first fluid flow path comprising an inlet that receives the oxygen-depleted gas from the reactor and an outlet that outputs oxygen-depleted gas with a reduced water content, and a heat absorption side in thermal communication with a heat sink including an inlet in communication with a source of aircraft ram air;
a liquid separator that separates water condensate produced by the heat rejection side of the first heat exchanger from the oxygen-depleted gas with reduced water content; and
a gas separator comprising a membrane permeable to water, comprising a first side of the membrane disposed along the first fluid flow path, the separator comprising an inlet on the first side of the membrane that receives the oxygen-depleted gas with reduced water content from the first heat exchanger and an outlet on the first side of the membrane that outputs dried oxygen-depleted gas, and a second side that receives water through the membrane from the oxygen-depleted gas with reduced water content, the separator comprising an outlet on the second side of the membrane that outputs a fluid comprising water.

2. The system of claim 1 , wherein the reactor comprises a catalyst that promotes reaction of oxygen with hydrocarbon to produce the oxygen-depleted gas comprising water vapor.

3. The system of claim 1 , further comprising a second heat exchanger comprising a heat rejection side disposed on the first fluid flow path between the reactor and the first heat exchanger, and a heat absorption side in communication with water from the liquid separator.

4. The system of claim 3 , wherein the heat absorption side of the second heat exchanger comprises an inlet that receives liquid water from the liquid separator and an outlet that outputs water vapor.

5. The system of claim 1 , wherein the second side of the gas separator comprises an inlet that receives a gas having a lower partial water vapor pressure than the oxygen-depleted gas with reduced water content.

6. The system of claim 5 , wherein the gas separator second side inlet is in communication with a source of aircraft ram air.

7. The system of claim 6 , wherein the heat absorption side of the first heat exchanger includes an outlet in communication with the gas separator second side inlet.

8. The system of claim 5 , wherein the gas separator second side inlet is in communication with a source of aircraft engine compressed bleed air.

9. The system of claim 1 , further comprising a vacuum pump in communication with the gas separator second side outlet.

10. The system of claim 1 , wherein the membrane comprises a polymer matrix that provides greater solubility to water molecules than nitrogen or oxygen molecules.

11. The system of claim 1 , wherein the source of gas comprising oxygen comprises a fuel tank gas space, and the source of hydrocarbon comprises the fuel tank gas space.

12. An on-board aircraft inert gas system, comprising
a source of hydrocarbon;
a source of a gas comprising oxygen;
a first fluid flow path between the source of gas comprising oxygen and an inert gas output;
a reactor disposed along the first fluid flow path comprising an inlet that receives hydrocarbon and the gas comprising oxygen and reacts the hydrocarbon with the oxygen to produce an oxygen-depleted gas comprising water vapor, and an outlet that outputs the oxygen-depleted gas comprising water vapor;
a first heat exchanger comprising a water-condensing heat rejection side disposed along the first fluid flow path comprising an inlet that receives the oxygen-depleted gas from the reactor and an outlet that outputs oxygen-depleted gas with a reduced water content, and a heat absorption side in thermal communication with a heat sink;
a liquid separator that separates water condensate produced by the heat rejection side of the first heat exchanger from the oxygen-depleted gas with reduced water content, and
a gas separator comprising a membrane permeable to water which comprises molecule size-selective tortuous paths that selectively allow faster transport of water molecules compared to nitrogen or oxygen molecules, with a first side of the membrane disposed along the first fluid flow path, the separator comprising an inlet on the first side of the membrane that receives the oxygen-depleted gas with reduced water content from the first heat exchanger and an outlet on the first side of the membrane that outputs dried oxygen-depleted gas, and a second side that receives water through the membrane from the oxygen-depleted gas with reduced water content, the separator comprising an outlet on the second side of the membrane that outputs a fluid comprising water.

13. The system of claim 12 , wherein the reactor comprises a catalyst that promotes reaction of oxygen with hydrocarbon to produce the oxygen-depleted gas comprising water vapor.

14. The system of claim 12 , further comprising a second heat exchanger comprising a heat rejection side disposed on the first fluid flow path between the reactor and the first heat exchanger, and a heat absorption side in communication with water from the liquid separator.

15. A method of making an inert gas, comprising:
reacting hydrocarbon and oxygen in a gas comprising oxygen to produce an oxygen-depleted gas comprising water vapor;
removing heat from the oxygen-depleted gas comprising water vapor to condense water vapor in a first heat exchanger cooled by a cooling air source including aircraft ram air, and removing condensate to produce an oxygen-depleted gas having reduced water content; and
contacting the oxygen-depleted gas having reduced water content with a membrane permeable to water to produce the inert gas comprising dried oxygen-depleted gas.

16. The method of claim 15 , further comprising removing water from the oxygen-depleted gas through the membrane.

17. The method of claim 15 , wherein reaction of hydrocarbon with oxygen in the fuel tank vapor is conducted with a catalyst that promotes reaction of oxygen with hydrocarbon to produce the oxygen-depleted gas comprising water vapor.

18. The method of claim 15 , wherein the oxygen-depleted gas having reduced water content has a water content of at least 2 g per kg of the oxygen-depleted gas.

19. The method of claim 15 , comprising contacting the oxygen-depleted gas having reduced water content with a first side of the membrane permeable to water, and contacting a second side of the membrane a gas having a lower partial water vapor pressure than the oxygen-depleted gas with reduced water content.

20. The method of claim 19 , wherein ram air exiting the heat exchanger is the gas directed to the second side of the membrane.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Cordatos Haralambos
• Rheaume Jonathan

Classifications

• B01D2258/01

  Engine exhaust gases · CPC title

• B01D2259/4575

  in aeroplanes or space ships · CPC title

• A62C3/08

  in aircraft {(A62C3/0207 takes precedence)} · CPC title

• B01D53/268

  by diffusion · CPC title

• B01D5/0003

  by using heat-exchange surfaces for indirect contact between gases or vapours and the cooling medium · CPC title