Human exploration activities on celestial bodies, such as the moon and mars, will produce human life support-derived wastes and consume fuel, water, and oxygen. Key waste streams to be expected…

This is a $749,972.37 cooperative agreement between the National Aeronautics and Space Administration (NASA) and the Louisiana Board of Regents, a state government agency responsible for coordinating public higher education in Louisiana. The agreement supports research and development of a Biochemical Conversion System (BIOSYS) to effectively treat human life support-derived waste streams (black water, grey water, food waste) during extended off-Earth excursions and produce beneficial byproducts such as fuels, recycled potable water, oxygen, protein, and lubricants. The research plan involves evaluating the performance of individual BIOSYS unit operations, integrating them into a bench system, and constructing a pilot system. The goal is to develop a compact, energy- and oxygen-efficient waste treatment system to reduce the need for expensive resupply missions. This work builds on the Louisiana Board of Regents' prior experience in converting wastewater into value-added products. There is no set-aside designation for this award, which has a completion date of May 16, 2023.

Human exploration activities on celestial bodies, such as the moon and mars, will produce human life support-derived wastes and consume fuel, water, and oxygen. Key waste streams to be expected include (1) black water (toilet-derived); (2) food wastes (kitchen-derived); and, (3) grey water (AKA. Hygiene water). Further, water and oxygen will both need to be conserved and recycled. Therefore, to sustain human life during extended off-earth excursions, recovery of the carbon, oxygen, and hydrogen along with the microchemicals making up the food, water, and air provided to the astronauts is needed to reduce the frequency of expensive makeup deliveries of these life support products. The technology used to recover resources must operate using compact, low weight designs; utilize minimal energy and oxygen footprints; be simple to operate with low maintenance; and, recover a high percentage of the life support resource chemicals that can placed back into beneficial use. The ideal system should also be flexible and contain built-in failsafe mechanisms that can adjust as unplanned events occur; yet, maintain operational capacity. The proposed biochemical conversion system (biosys) will effectively treat all human activity-derived waste (black water, grey water, and food waste streams) while producing beneficial by-products: fuels, recycled potable water, oxygen, protein cake, and machinery lube oils. The biosys concept is based on a series of successful projects performed by the project team over the past 15 years that focused on converting wastewater into value-added products. The key development goals for the biosys project are (a) be energy and oxygen use neutral; (b) have a compact process footprint and low payload weight; (c) be capable of treating water and air to reusable qualities; and, (d) be capable of producing CO-products that can also be used for life support. The primary biosys concept design utilizes a series of treatment steps to convert wastewater constituents and cabin CO2 into recovered beneficial life support products. The design is composed of both anaerobic and aerobic bioreactor units; lipids extraction; a microalgae reactor; and an adsorption polishing step. This design results in the treatment of the contaminants in the water to essentially zero concentrations. Several products will be produced as system outputs: (1) hydrogen - fuel for fuel cells; (2) methane - also as fuel for fuel cells or potentially FED into the aerobic bioreactor for producing more protein and/or lipids; (3) recovered O2 - recycled back into the cabin environment; (4) lipids - production of green lube oils or used as a nutraceutical; (5) protein cake (with or without lipids) - a food source; (6) soil amendments - fertilizer; and, (7) recovered water - recycled as potable water. One challenge could be oxygenating the aerobic unit which causes an oxygen sink that may be too costly. Hence, to reduce energy/oxygen use, a design option which eliminates the aerobic stage and replaces IT with a passive solids separator will be considered. The research plan involves evaluation of each unit operation performance via small reactor systems operated using a wide variation of feed rates and composition to test normal and stressed performance. Optimized individual units will be integrated into a bench system that will, in turn, be evaluated for its operational performance under stress. Mass and energy balances across the entire system and in between each unit operation will be used to optimize the performance of the bench system. A pilot system will be constructed based on the work done in the bench phase and its performance will be evaluated. Payloads and systems operation protocols will be evaluated and included as part of a comprehensive design evaluation. Publications including reports, peer-reviewed papers, and presentations will be key products along with outreach to recruit future stem majors interested in space exploration.