In-situ resource utilization (ISRU) has been proposed for processing water-ice on the Moon and Mars to provide fresh water, breathable oxygen, and rocket propellant for future exploration missions. On the Moon, evidence of water-ice has been detected in permanently shadowed regions (PSR) concurrently with other non-water volatile (NWV) species. On Mars, water-ice or brines have been detected at or below the surface in mid and high latitudes. Paragon Space Development Corporation has been developing the ISRU Collector of Ice in a Cold Lunar Environment (ICICLE) technology to specifically target the simultaneous capture and coarse purification of lunar water via deposition from an upstream sublimation-driven extraction process. The development of this technology has included model development for expected NWV retention with collected water, proof of concept experimentation for the "freeze distillation" of water, model development of the water deposition process, and TRL 4 demonstration of a sub-scale prototype collecting water at internally relevant process conditions. In this paper, we revisit the initial model for lunar NWV retention with collected water in order to study the effect of envelope conditions under which lunar water extraction and collection may occur. Whereas the initial model was focused on a single operating point as a case study, the present work describes all viable operating points for the ICICLE technology and the implications for downstream water purification and electrolysis systems.
Holquist et al. (Sun,) studied this question.