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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.

Poly (vinyl chloride) (PVC) matrix membranes which incorporate the ionophore nonactin have been evaluated as cation exchange membranes for ammonium ion transport in an electrolytic cell configuration. Interest exists for the development of cation selective membranes for removal of low levels (<200ppm) of ammonium ions commonly found in recycled effluent streams in such diverse applications as expected in a Space Station and commercial fisheries. Ammonium ions are generated as a decomposition product of urea and over time build up in concentration, thus rendering the water unsuitable for human consumption. Nonactin is commonly used in a PVC matrix for ion-selective electrodes.

The purification of reclaimed water is essential to water reclamation technology life-support systems in lunar/Mars habitats. Lynntech, Inc., working with NASA-JSC, is developing an electrochemical UV reactor which generates oxidants, operates at low temperatures and requires no chemical expendables. The reactor is the basis for an advanced oxidation process, in which electrochemically generated ozone and hydrogen peroxide are used, in combination with ultraviolet light irradiation, to produce hydroxyl radicals. Results from this process are presented which demonstrate concept feasibility for removal of organic impurities and disinfection of water for potable and hygiene reuse. Power, size requirements, Faradaic efficiency and process reaction kinetics are discussed. At the completion of this development effort, the reactor system will be installed in JSC's regenerative water recovery test facility for evaluation to compare this technique with other candidate processes.

The recovery of potable water from waste water produced by humans in regenerative life support systems is essential for success of long-duration space missions. The Lunar-Mars Life Support Test Project (LMLSTP) Phase II test was performed to validate candidate technologies to support these missions. The test was conducted in the Crew and Thermal Systems Division (CTSD) Life Support Systems Integration Facility (LSSIF) at Johnson Space Center (JSC). Discussed in this paper are the water recovery system (WRS) results of this test. A crew of 4-persons participated in the test and lived in the LSSIF chamber for a duration of 30-days from June 12 to July 12, 1996. The crew had accommodations for personal hygiene, the air was regenerated for reuse, and the waste water was processed to potable and hygiene quality for reuse by the crew during this period. The waste water consisted of shower, laundry, handwash, urine and humidity condensate.

The impact on the water recovery and reclamation system resulting from laundry operations has been the primary obstacle to the implementation of a laundry capable for long duration space missions. Such an onboard system can provide improved housekeeping effectiveness and crew health maintenance aspects. Electrochemically generated ozone was used as a laundry (cleaning) agent under simulated washing conditions and compared with Tide® and dodecynlbenzoicsuccinic acid (DBSA). Three aspects were studied: (i) cleaning ability; (ii) disinfection potential; and, (iii) impact on the resulting laundry water. In most instances, ozone provided a detergent-like cleaning ability that was as good as, or better than, Tide® or DBSA. Ozone was a superior disinfectant and, more importantly, had a low impact on the laundry wash water in terms of its potential for recycling.

A Total Organic Carbon (TOC) Analyzer has been developed for a Life Sciences Risk Mitigation Flight Experiment to be conducted on Spacehab and the Russian space station, Mir. Initial launch is scheduled for December 1996 (flight STS-81). The analyzer will be tested on the Orbiter in the Spacehab module, including when the Orbiter is docked at the Mir space station. The analyzer is scheduled to be launched again in May 1997 (STS-84) when it will be transferred to Mir. During both flights the analyzer will measure the quality of recycled and ground-supplied potable water on the space station. Samples will be archived for later return to the ground, where they will be analyzed for comparison to in-flight results. Water test samples of known composition, brought up with the analyzer, also will be used to test its performance in microgravity. Ground-based analyses of duplicates of those test samples will be conducted concurrently with the in-flight analyses.