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Problem: Do you need nitrogen-enriched air (NEA) on demand and from reliable, small, lightweight equipment? (back to top)   Solution: Carleton Life Support can provide systems containing PRISM® membranes to qualify for the most demanding aerospace OBIGGS applications. Air Products manufactures a membrane separator targeting the low-weight, high-temperature requirements specified for the aerospace industry. This PRISM membrane has the smallest components list in the membrane industry, making it extremely reliable. Contact Carleton Life Support to find out what an OBIGGS based on PRISM membranes can do. Contracts: With our licensed partner, Carleton Life Support Systems, Air Products was selected by Boeing to supply the nitrogen membrane to produce nitrogen enriched air (NEA) for the Air Force C-17 Globemaster III.  Boeing also selected Carleton and Air Products to supply the NEA for the new Boeing 7E7 DreamLiner due to launch in 2008. The Air Products PO series membrane was chosen for its unsurpassed reliability and robustness. (back to top)   Benefits: Demonstrated shock and vibration performance. Fewest components per membrane in the industry. Good resistance to water and oil vapor contamination. Low maintenance. No moving parts. Lightweight and compact. Easy to incorporate into OEM equipment. Adjustable purity. Flow, temperature and pressure variables allow the PRISM membrane to generate up to 99.9% purity. Simple to use. Eliminates the need for nitrogen cylinders. (back to top)   Example: F-22 Aircraft The first membrane-based OBIGGS for the F-22 used PRISM membranes. PRISM membrane devices exceeded design expectations for cumulative flight hours in the F-22. PRISM membranes designed for OBIGGS applications use a lightweight aluminum pressure vessel designed specifically for each application. (back to top)   Related Publications: Anderson, C. L. AD-A198 Advanced Air Separation Module Performance Evaluation Final Report (AFWAL-TR-88-2031) July 1988 (Available for purchase from NTIS). (back to top)   Frequently Asked Questions: Will PRISM membranes be damaged by liquid water and oil? PRISM membranes will not be permanently damaged by liquid water. The membrane performance can be restored by flowing warm, dry air through the membrane until all the liquid water is removed. The membranes will not be affected by oil vapor in the feed stream; however, the membranes will be permanently damaged by liquid oil entering or condensing in the membrane. Upstream filtration is recommended to ensure all oil aerosols are removed. Can I replace the fiber if the device becomes damaged? The fiber is not repairable or replaceable. However, with routine maintenance of the upstream filtration, membrane life is expected to be ten years. Of course, individual PRISM membrane devices can be replaced to return an OBIGGS to optimum performance. What is the dew point of the nitrogen that is produced by the membrane? The dew point varies slightly with nitrogen purity. At 95% purity, the nitrogen will have at least a –70°F dew point. Operating at 99% will further lower the dew point to below –100°F. What does a PRISM membrane OBIGGS weigh? The weight is strongly dependent upon the system performance required. Separators weighing 5 to 20 pounds have been considered for various OBIGGS applications. Air Products can select from several materials to design and build membrane separators. These materials can save weight while meeting temperature and pressure requirements. In addition, we have developed manufacturing processes and designed custom components to keep device weight to a minimum. How long will OBIGGS systems with PRISM membranes provide adequate performance? Device performance lifetime is a function of the filtration provided and the environment in which they are operated. Air Products membrane separators have operated for more than 10 years in numerous refinery installations involving heavy hydrocarbons. Prototype OBIGGS separators have been operated for more than 1100 continuous hours at 225°F before ending testing. No performance or mechanical failures have been found after this testing. In addition, the membrane performance is stable over time. Performance change has been projected to be less than 10% across 20,000 hours of operation at 225°F. (back to top)