1. High Temperature Membrane for OBIGGS Application
Honeywell
High Temperature Membrane for OBIGGS Application
Lisbon
11/15/2004
Jim Zhou

2. Outline
Objectives
Why high temperature membrane?
Fiber spinning conditions
Test results
Conclusions

3. Why high temperature membrane?
Objectives
Objectives
To develop a high temperature gas separation hollow fiber membrane suitable for the OBIGGS application
Why high temperature membrane?
Reduce the size and volume of the OBIGG system by taking advantage of higher gas permeability at higher temperatures and reduced cooling requirements at higher OBIGGS operating temperature

4. Membrane Material Selection
Honeywell’s Innovative High Temperature Membrane
High O2, N2 permeability
High O2/N2 Selectivity
Wet spun with very thin selective layer to increase flux
Less susceptible to contaminants
Large operating temperature and pressure range

5. Membranes and Membrane Modules
Nitrogen
Oxygen
Water Vapor
Nitrogen
Oxygen and water vapor are “fast” gases which quickly permeate the membrane, allowing nitrogen to flow through the fiber bores as the product stream.
Feed Air
This illustration shows how fast gases like oxygen and moisture permeate the surface of the individual membrane fibers while nitrogen molecules remain inside and are delivered as the product gas.

6. Membranes and Membrane Modules
End Plate
Epoxy Tube Sheet
Enriched Nitrogen Product Gas
Support Core
Epoxy Tube Sheet
Oxygen- Enriched Air
Hollow Fibers
Feed Air
O-Rings
Thousands of individual fibers wrapped around a core make up the nitrogen generating hollow fiber membrane module. The engineering of the module is important to maximizing the performance of the whole system.

7. Fiber Spinning Conditions
Phase inversion/Wet spinning process
Pros
Can produce membrane with extremely thin selective layer (Asymmetrical membrane structure)
Cons
Porous support layer may not be stable at high temperatures
Complex spinning and solvent leaching process
Membrane selectivity changes with the amount of solvent left behind

8. Typical Fiber Spinning Conditions
Fiber spinning condition ranges
Polymer dope rate: 1.2 to 2.5 g/min/per strand
Speed: 75 to 250 ft/min(23 to 76 m/min)
Center solvent rate: 0.5 to 2.0 ml/min
Temperature: Room to 100oC
Fiber ID: 100 to 160 micron
Fiber OD: 150 to 300 micron

9. Membrane Structure
Thin skin layer with porous support
High gas flux

10. Test Results

11. Test Results

12. Test Results

13. Air Separation Modules

14. Conclusions Membrane is stable at operating temperatures up to 160C
Membrane flux increase with increase temperature
Membrane performance influenced by spinning conditions
High temperature membrane offers advantages over conventional membranes

15. The Fourth Triennial International Aircraft Fire and Cabin Safety
Research Conference
The Fourth Triennial International Aircraft Fire and Cabin Safety
Research Conference