Continued Development of a Liquid Amine Carbon Dioxide Removal System for Microgravity Applications

Carbon dioxide (CO2) can rapidly accumulate in spacecraft, creating a dangerous breathing environment if not properly controlled. Traditionally, solid adsorbents have been used to capture and release the CO2 generated by crew metabolic activity. Liquid absorbents have generally been avoided, due to the added complexity of handling fluids in a microgravity environment. However, with the advent of advanced manufacturing techniques using three-dimensional printing, a capillary-based gas/liquid contactor and degasser system has been developed and tested. Test data and an accompanying mathematical model have been developed for the contactor portion of the system. Flux rate data were then used to size a concept for application in a spacecraft. Finally, an integrated test stand was configured with the degasser and thermal control equipment. The integrated test stand was operated in a bench-scale format, confirming that the sizing analyses are realistic. A process model for the overall system developed in previous efforts was updated with all of the data collected during the most recent fiscal year. In aggregate, the results of parallel experimentation and modeling efforts continue to be encouraging for alternative liquid amine-based CO2 capture system.