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The recovery of resources for reuse from the processing of diverse waste materials produced by a crew in space-based closed life support systems is essential for the success of long duration space missions. Lynntech, Inc. is investigating and developing a waste processor that uses thermal solubilization and wet oxidation at elevated pressure and an electrochemical process for solid waste processing for closed life support systems. The electrochemical process uses a packed bed anode that oxidizes waste at temperatures <100°C and operates at atmospheric pressure. This approach offers an alternative to high temperature thermal processes for solid waste treatment. Incorporated into the packed bed reactor design is a method that shows potential for regenerating a liquid electrolyte enabling the electrochemical process to operate for long periods without having to be replaced.

The post-treatment purification of water recovered from hygiene, metabolic and humidity condensate waste water is essential to regenerative water reclamation technology life support systems. Lynntech, Inc., working with NASA-JSC has developed an electrochemical reactor that generates ozone and hydrogen peroxide. The electrochemical reactor is the basis for an advanced oxidation process in which electrochemically generated oxidants are used in combination with ultraviolet irradiation to produce hydroxyl radicals in a reclaimed water stream which in turn oxidize dissolved organic impurities to carbon dioxide. This paper describes the design and fabrication of an automated breadboard reactor system based on this principle. The system operates at low temperature and requires no chemical expendables. Kinetics and performance test results are presented showing the removal of organic impurities and disinfection features to produce potable water quality.

Water reclamation subsystems currently being evaluated for the Space Station Freedom are designed primarily to reclaim water from waste streams containing low to moderate levels of organics/inorganics, including chemical additives to control microorganism proliferation. Wastes containing high organic content (solids), especially those containing chemical and bioprocess fluids, present potential risks for compromising operational integrity of these subsystems. Looking beyond near-term needs to reclaim water from primarily crew-derived waste streams, refurbishment and process characterization of a waste water management system capable of processing wastes containing high concentrations of organic/inorganic materials has been initiated. The process combines low temperature/pressure to vaporise water with high temperature catalytic oxidation to decompose volatile organics. The reclaimed water is of potable quality and has a high potential for maintenance under sterile conditions.