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Archival sampling of potable water and condensate for ground laboratory analysis has been an important part of the Shuttle-Mir program because of coolant leaks and other events on Mir that have affected water quality. We report here the development of and preliminary results from a novel device for single phase humidity condensate collection at system pressures. The sampler consists of a commercial-off-the-shelf Teflon® bladder and a custom reinforced Nomex® restraint that is sized properly to absorb the stress of applied pressures. A plastic Luer-Lock disconnect, with poppet actuated by a mating Luer-Lock fitting, prevents the contents from being spilled during transport. In principle, a sampler of any volume can be designed. The empty mass of the reusable one-liter sampler is only 63 grams. Several designs were pressure tested and found to withstand more than 3 atmospheres well in excess of typical spacecraft water or wastewater system pressures.

On the International Space Station (ISS), atmospheric humidity condensate and other waste waters will be recycled and treated to produce potable water for use by the crews. Space Station requirements include an on-orbit capability for real-time monitoring of key water quality parameters, such as total organic carbon (TOC), total inorganic carbon (TIC), total carbon (TC), pH, and conductivity, to ensure that crew health is protected during consumption of reclaimed water. The Crew Health Care System (CHeCS) for ISS includes an analyzer that has been designed to meet this requirement. The analyzer is adapted from commercially successful technology, and it measures TOC and TIC throughout the range from 1 to 50,000 μg/L, and TC from 1 to 100,000 μg/L. It measures pH between 2.0 and 12.0 pH units, and conductivity from 0.1 to 300 μmho/cm. The analyzer is scheduled for launch to ISS on mission 2A.1.

At the initial phase of the construction of the international space station (ISS) water supply will be provided by the systems located in the Russian segment. The paper reviews the systems for water recovery from humidity condensate and urine to be incorporated in the Russian segment of the ISS. The similar systems have been successfully operated on the Mir space station. The updates aim at enhancing system cost-effectiveness and reliability. The system for water recovery from humidity condensate (WRS-C) features an added assembly for the removal of organic contaminants to be catalytically oxidized in an air/liquid flow at ambient temperature and pressure. The system for water reclamation from urine (WRS-U) incorporates a new distillation subsystem based on vacuum distillation with a multistage rotary distiller and a vapor compression or thermoelectric heat pump. The updating of the WRS-C system will enable an increase in the multifiltration bed's life at least two fold.

A filter assembly which is incorporated into the Russian Trace Contaminant Control Assembly was tested for removal of airborne trace chemical contaminants in a closed loop 9 m3 system. Given contaminant loading rates and maximum allowable atmospheric concentrations, the Russian system was able to maintain system air concentrations below maximum allowable limits. This was achieved for both a new filter system and for a system where a part of it was pre-loaded to emulate 3 years of system age.

On the International Space Station (ISS), atmospheric humidity condensate and other waste waters will be recycled and treated to produce potable water for use by the crews. Space station requirements include an on-orbit capability for real-time monitoring of key water quality parameters, such as total organic carbon, total inorganic carbon, total carbon, pH, and conductivity, to ensure that crew health is protected for consumption of reclaimed water. The Crew Health Care System for ISS includes a total organic carbon (TOC) analyzer that is currently being designed to meet this requirement. As part of the effort, a spacecraft TOC analyzer was developed to demonstrate the technology in microgravity and mitigate risks associated with its use on station. This analyzer was successfully tested on Shuttle during the STS-81 mission as a risk mitigation experiment. A total of six ground-prepared test samples and two Mir potable water samples were analyzed in flight during the 10-day mission.

The primary source of potable water planned for the International Space Station will be generated from the reclamation of humidity condensate, urine, and hygiene waters. It is vital to crew health and performance that this reclaimed water be safe for human consumption, and that health risks associated with recycled water consumption be identified and quantified. Only recently has data been available on the chemical constituents in reclaimed waters generated in microgravity. Results for samples collected during Mir-21 reveal that both the reclaimed water and stored water are of potable quality, although the samples did not meet U.S. standards for total organic carbon (TOC), total phenols, and turbidity.

This report describes the first two parts of a three-phase project to develop and test a spacecraft-compatible capillary electrophoresis (CE) instrument. This instrument is designed to monitor the quality of recycled potable water aboard spacecraft such as the International Space Station. Phase I involved selecting and validating methods for low mass-to-charge ratio (m/z) cations and anions by using a slightly modified commercial CE instrument as a model. The analytical performance of several published CE methods was assessed for their ability to detect targeted anions and cations listed in a NASA water quality standard. Direct and indirect UV absorption detection at a single wavelength (214 nm) was used, and separation selectivity and sensitivity were optimized at the expense of analysis time. Phase II focused on building a breadboard CE instrument and flight-testing it on NASA's KC-135 parabolic aircraft.

To satisfy a requirement to supply water to Mir station, a process for treating iodinated water on the Shuttle was developed and implemented. The treatment system consists of packed columns for removing iodine and a syringe-based injection system for adding ionic silver, the biocide used in Mir water. Technical and potable grade water is produced and transferred in batches using collapsible 44-liter contingency water containers (CWCs). Silver is added to the water via injection of a solution from preloaded syringes. Minerals are also added to water destined for drinking. During the previous four Shuttle-Mir docking missions a total of 2781 liters (735 gallons) of water produced by the Shuttle fuel cells was processed using this method and transferred to Mir. To verify the quality of the processed water, samples were collected during flight and returned for chemical analysis.

An important milestone in the ongoing effort by NASA to develop and refine closed-loop water recycling systems for human space flight was reached during the summer of 1996 with the successful completion of Phase II of the Lunar Mars Life Support Testing Program at Johnson Space Center. Part of Phase II involved testing a water-recycling system in a closed test chamber continuously occupied by four human subjects for thirty days. The Phase II crew began the test with a supply of water that had been processed and certified for human use. As the test progressed, humidity condensate, urine, and wastewater from personal hygiene and housekeeping activities were reclaimed and reused several times. Samples were collected from various points in the reclamation process during the thirty day test. The data verified the water-processing hardware can reliably remove wastewater contaminants and produce reclaimed water that meets NASA standards for hygiene- and potable-quality water.

This paper reviews designs of urine distillation systems for spacecraft water recovery. Consideration is given to both air evaporation and vacuum distillation cycles, to the means for improving cycle performance (such as heat pumps, multistaging, and rotary evaporators), and to system concepts offering promise for future development. Vacuum distillation offers lower power consumption, at some increase in system complexity; air evaporation distillation is capable of providing higher water recovery efficiency, which could offset the lower power consumption advantage of vacuum distillation for long-duration missions.

The ability to aseptically remove samples and products, and the capability for addition of materials to sterile or otherwise microbially susceptible systems have always been compromised by the lack of a reliable means of sterilizing the mating fixtures. Cultures of mammalian cells are particularly vulnerable to microbial contamination due to the complexity of nutrient media and the lengthy periods required for cell growth. The Microwave Sterilizable Access Port has been developed to overcome this limitation. The system consists of three primary components: a microwave power source, a combined sterilization chamber/in-line valve port assembly, and a specimen transfer interface. Microwave energy is transmitted via coaxial cable to a small pressurized chamber that serves as a sterile transition between the surrounding environment and the system during transfer of materials.

Potable- and hygiene-quality water will be supplied to crews on the International Space Station through the recovery and purification of spacecraft wastewaters, including humidity condensate, urine, and wash water. Contaminants released into the cabin air from human metabolism, hardware offgassing, flight experiments, and routine operations will be present in spacecraft humidity condensate; normal constituents of urine and bathing water will be present in urine and untreated wash water. This report describes results from detailed analyses of Mir reclaimed potable water, ground-supplied water, and humidity condensate. These results are being used to develop and test water recycling and monitoring systems for the International Space Station (ISS); to evaluate the efficiency of the Mir water processors; and to determine the potability of the recycled water on board.

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.

A concept of LSS building for planetary stations is suggested on the basis of experience in the development, research and testing of physical/chemical regenerative LSS for long-duration ground-based bio-technical complexes of habitat support and for orbiting space stations. A gradual transition from integrated physical/chemical regenerative LSS to hybrid integrated physical/chemical and bio-technical LSS and finally to integrated bio-technical regenerative LSS, is suggested. It is shown that at all phases of integrated LSS development, the systems based on physical/chemical processes will be critical for correlating the interfaces between the biological components that process the products obtained in the bio-components, and enabling the vitality of integrated LSS under emergency situations. The interface of integrated LSS with base power supply system is outlined.

The paper reviews an integrated system for space station water supply based on a combination of water recovery systems and a water resupply system. The water balance data and system performance data in long-duration operation on the Mir space station are presented. A water supply concept for the Russian's segment (RS) of the International Space Station (ISS) is substantiated.

The paper deals with possible performance enhancement of the system for water reclamation from urine based on a principle of atmospheric distillation. It is shown by way of example using the system operating on Mir that the introduction of heat energy recuperation, an increase in heat-and-mass transfer efficiency on evaporation and the optimization of the air flowrate in the distillation cycle allow a rise in the capacity of the distillation assembly and a reduction in specific energy. The system outfitted with a rotary evaporator/separator and a thermoelectric heat pump is reviewed. The design and experimental data verify the feasibility and benefits of the system updating.

On the International Space Station (ISS), humidity condensate will be collected from the atmosphere and treated by multifiltration to produce potable water for use by the crews. Ground-based development tests have demonstrated that multifiltration beds filled with a series of ion-exchange resins and activated carbons can remove many inorganic and organic contaminants effectively from wastewaters. As a precursor to the use of this technology on the ISS, a demonstration of multifiltration treatment under microgravity conditions was undertaken. On the Space Shuttle, humidity condensate from cabin air is recovered in the atmosphere revitalization system, then stored and periodically vented to space vacuum. A Shuttle Condensate Adsorption Device (SCAD) containing sorbent materials similar to those planned for use on the ISS was developed and flown on STS-68 as a continuation of DSO 317, which was flown initially on STS-45 and STS-47.

One of the proposed methods for monitoring the microbial quality of the water supply aboard the International Space Station is membrane filtration. We adapted this method for space flight by using an off-the-shelf filter unit developed by Millipore. This sealed unit allows liquid to be filtered through a 0.45 μm cellulose acetate filter that sits atop an absorbent pad to which growth medium is added. We combined a tetrazolium dye with R2A medium to allow microbial colonies to be seen easily, and modified the medium to remain stable over 70 weeks at 25°C. This hardware was assembled and tested in the laboratory and during parabolic flight; a modified version was then flown on STS-66. After the STS-66 mission, a back-up plastic syringe and an all-metal syringe pump were added to the kit, and the hardware was used successfully to evaluate water quality aboard the Russian Mir space station.

This paper describes the results of research and tests of different patterns of distillation processes for water reclamation from urine accomplished by NIICHIMMASH in cooperation with other companies. Several typical patterns of evaporation to air flow from water-retentive porous bodies, from the surface confined by capillary/porous membranes and from free liquid surface in rotary units under atmospheric and reduced pressure are analyzed. Relevant condensation processes are reviewed. Performance data for distillation unit of SS MIR system for water reclamation from urine are outlined. The paper highlights the prospects of distillation hardware development.

The paper analyzes and summarizes experience in developing and flight operation of the system for potable water recovery from humidity condensate. The system schematic and its hardware are reviewed. The system performance data on Salut and Mir space stations are presented. Succession to the development of a similar system for the International Space Station (ISS) service module is shown.