Holistic Resource Management for Sustainable Life Support beyond Low-Earth Orbit: Focus on Nitrogen



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51st International Conference on Environmental Systems


A half century of manned space exploration engendered performant technology to support human life onboard the International Space Station (ISS). A protective and conditioned habitat with provision of water and oxygen are the crucial elements of the Environmental Control and Life Support System. Currently, onboard the ISS, resupply of water and food complement the resources obtained from partial recycling of metabolic waste products including urine, condensate and carbon dioxide. Clean water is produced from the liquid waste by a series of physicochemical processes. Carbon dioxide from the cabin air is concentrated on adsorbers and converted into water and methane by catalytic reduction using hydrogen. Oxygen is produced by the electrolysis of water. Long-term human space exploration on planetary surfaces like the Moon and Mars requires an even higher recycling rate of the other essential elements including carbon, nitrogen, phosphorus and minerals to produce food and other consumables. A combination of in situ-resource utilization (ISRU) and integral recycling of all waste products will determine the configuration of next-generation Life Support technology. Interactions between physical, chemical and (micro)biological processes require a holistic engineering approach to develop sustainable Life Support Systems (LSSs). Multiple disciplines among process and chemical engineering, bio-engineering, geo-engineering besides space engineering, having traditionally a dominant focus on mechanical or electrical aspects, will unite. Recycling technology will no longer be approached as an assembly of �sub-systems� but as interaction of �processes�. Waste recycling and ISRU rely on common fundamental processes including transformation by oxidation-reduction, separation and concentration. Whether the processes are physically, chemically or (micro)biologically driven, the thermodynamic laws and conservation of mass apply. Candidate technology will be evaluated by a design methodology evaluating yields and efficiencies normalized against required energy and system weight and volume. Reliability, safety and operational aspects complement the trade-off matrix for configuring (bio)regenerative LSSs.


Dries Demey, QinetiQ Space nv, BE
Marie Vandermies, QinetiQ Space nv, BE
ICES204: Bioregenerative Life Support
The 51st International Conference on Environmental Systems was held in Saint Paul, Minnesota, US, on 10 July 2022 through 14 July 2022.


holistic engineering, design methodology, bioregenerative Life Support, metabolic waste, resource recovery, food production, in-situ resource utilisation, oxidation-reduction, microbial processes