Closing the ECLSS loop and recycling more carbon dioxide (CO2) will allow for longer duration human space missions like Mars transit; however, CO2 that has been removed from the air must be pressurized and stored before being recovering the oxygen. The Air-Cooled Temperature Swing Adsorption Compression system (AC-TSAC) is an alternative CO2 compression, storage, and regulation system that interfaces between CO2 removal and conversion systems with improved performance and lower size, weight, and power compared to the mechanical compressor and tanks in use now. AC-TSAC has been previously integrated and tested with the ground version of successful flight CO2 removal systems like Carbon Dioxide Removal Assembly (CDRA) and Four bed CO2 scrubber (4BCO2). In this work, efforts to redesign the AC-TSAC system to meet the demands of current CO2 removal systems are reported. AC-TSAC operation was adjusted to match shorter cycle times of CO2 removal systems being demonstrated on the International Space Station: 4BCO2 (80 min) and thermal amine scrubber (TAS; 60 min), as previous AC-TSAC hardware was designed to match CDRA (144 min). The old commercially unavailable sorbent was changed out to a newer readily available sorbent (Grace 544 13X; same as in 4BCO2) and power use was studied in simplified experiments. Additionally, thermal modeling was done to optimize the bed design by iterating several bed design factors including fin length and thickness. With these updates, AC-TSAC should be able to better integrate and see improved performance with current CO2 removal systems.
Wells et al. (Sun,) studied this question.