Long-Duration Testing of a Temperature-Swing Adsorption Compressor for Carbon Dioxide for Closed-Loop Air Revitalization Systems 2005-01-2942

This paper describes the results of an ongoing long-duration testing of a temperature-swing adsorption compressor (TSAC) that has application in closing the air revitalization loop of the International Space Station (ISS) and future spacecraft. The TSAC is a solid-state compressor that has the capability to remove CO₂ from a low-pressure source, and subsequently store, compress, and deliver it at a higher pressure as required by a processor. The TSAC described in this paper was designed to function as an interface device for the CO₂ removal and reduction units of the International Space Station (ISS). The air revitalization system of the ISS operates in an open loop mode and relies on the resupply of oxygen and other consumables from Earth for the life support of astronauts. A compressor is required for recovering the CO₂ from the carbon dioxide removal assembly (CDRA) and delivering to a CO₂ reduction unit of an oxygen recovery system and thereby closing the air-loop. The TSAC achieves suction and compression of the CO₂ through heating and cooling of the adsorbent enclosed in a chamber. The TSAC was developed at NASA Ames Research Center (ARC) and its operation was successfully verified in integration tests with the flight-like CDRA at Marshall Space Flight Center prior to the long-duration tests. The purpose of the long-duration tests is to reveal any impacts of the repeated thermal cycling on the compressor components and the adsorbent material.