Regenerable Trace Contaminant Control for Advanced Portable Life Support System

The Trace Contaminant Control (TCC) System is a component in the Exploration Portable Life Support System (xPLSS) which removes contaminants present in the ventilation loop. These trace contaminants, introduced into the ventilation loop via crew metabolic processes, off-gassing of spacesuit materials, and by-products of the suit processes, such as the CO2/H2O removal system (e.g., Rapid Cycle Amine beds), would accumulate without the TCC and pose a threat to the crewmember. Trace contaminants are traditionally removed using non-regenerable activated carbon. While effective, the downside of the current state-of-the-art is a high associated life cycle operating cost resulting from a low regeneration capability, a large canister size, and significant power consumption during regeneration. This provides a logistics impact for future missions.
Precision Combustion, Inc. (PCI) has continued its development of a compact, vacuum-regenerable sorbent bed for effectively removing a broad range of trace contaminants, including ammonia, meeting NASA’s target performance requirements, which can be integrated with the xPLSS CO2/H2O removal system. Both the primary trace contaminants as well as other species that threaten to exceed the 7-day Spacecraft Maximum Allowable Concentration (SMAC) levels are addressed. PCI’s proven sorbent nanomaterials have high surface area on a structured support, enabling a compact, modular, and vacuum-regenerable TCC device. Current development efforts have focused on design optimization to reduce the pressure drop of the TCC canisters and extend their protection periods for the contaminants of concern. In this paper, performance data will be presented for the second generation TCC hardware prototypes integrated with a CO2/H2O removal system in a closed-loop ventilation test rig. Additionally, results from sorbent testing with multiple trace contaminants under PLSS operating conditions will be presented, including capacity, regenerability, and multi-cycle performance. The performance of an integrated, vacuum-regenerable TCC bed for multi-contaminant adsorption will be presented along with future maturation steps.