Low Power Medical Oxygen Concentrators for Space Missions

An onboard oxygen concentrator is required during long duration manned space missions to supply medical oxygen. The commercial medical oxygen generators based on pressure swing adsorption (PSA) are large and highly power intensive. TDA Research, Inc. is developing a small, lightweight, portable oxygen generator based on a vacuum swing adsorption (VSA) to produce concentrated medical oxygen. The unit uses ambient vehicle cabin air as the feed and delivers high purity oxygen while meeting NASA's requirements for high flow capacity, closed loop tissue oxygen control and operation in microgravity/partial gravity. TDA's VSA system uses a modified version of the lithium exchanged low silica X zeolite (LiLSX), a state of the art air separation sorbent extensively used in commercial Portable Oxygen Concentrators (POCs) to enhance the N2 adsorption capacity. With this sorbent, we are able to design and fabricate small compact modules that are capable of generating up to 4 SLPM of medical grade oxygen. All together 4 units will connect to a head unit that will serve as a manifold to provide a total oxygen delivery rate of 16 SLPM with closed loop control based on the patient requirements. Test results of the modular prototype medical oxygen concentrator under various operating conditions of interest including simulated microgravity and partial gravity atmospheres inside a vacuum chamber will be presented at the meeting.