Hybrid Air Revitalization System for a Closed Ecosystem 901311

For future extended duration, manned missions, development of life support systems that require minimum expendables, power, weight and volume are essential. The ability to produce useful materials with minimum processing by using metabolic and life support byproducts is also of great importance. Life Systems, working with the National Aeronautics and Space Administration - Johnson Space Center, has been investigating various combinations of physical, chemical, electrochemical and biological methods for this purpose. ^(I)*

This paper describes a closed ecosystem air revitalization concept, called a Hybrid Air Revitalization System, that uses higher plants in a plant habitat for removing metabolic carbon dioxide and moisture for their photosynthesis while producing oxygen and supplemental food for crew consumption. The system includes Electrochemical Carbon Dioxide and Oxygen Separators and a moisture condenser/separator for maintaining carbon dioxide, oxygen, humidity and temperature levels in the crew and the plant habitats at their respective optimal conditions. This paper also presents the functional mechanisms of the separators, flow configurations and an example of system mass balance. Test results of one of the key components in the system, the Electrochemical Carbon Dioxide Separator (without using hydrogen), are also presented.