Lucia Grizzaffi

Quality of ATV Potable Water for ISS Crew Consumption

Potable water is undoubtedly one of the most critical resources for the International Space Station (ISS) crews. The amount and quality of this resource, mainly provided to the ISS by the Space Shuttle and Progress, and in the near future by logistic vehicles Automated Transport Vehicle (ATV) and HTV, must be compatible with the crew consumption needs and health-related requirements. For this purpose, potable water must satisfy very stringent quality requirements from chemical and bacteriological point of view. The definition of such requirements, resulting from medical studies, lessons learned, technical constraints, is reached in agreement among ISS International Partners. Two different quality standards are defined, one for the ISS Russian Segment, the other for the US Segment and other International Partners. The ATV, a program under European Space Agency (ESA) contract and EADS Space Transportation (EST) prime contractor-ship, is the only logistic vehicle requested to transport and deliver potable water to ISS according to both quality standards. Significant efforts have been spent in Alenia Spazio, responsible for the ATV Integrated Cargo Carrier, to define all the activities necessary to accomplish this task. The main aspects under consideration have been: selection of materials in contact with water, identification of suitable potable water sources, water preparation and disinfection, and pre-conditioning of equipment. This paper focuses on preparation and quality of potable water as obtained in dedicated ground facilities. The quality and stability of source water are an essential pre-requisite to attain the required standards. Disinfection techniques using colloidal silver and iodine are discussed, and their implementation in the ATV Water Preparation Facility at Societa Metropolitana Acque Torino (SMAT) premises is presented. The results of chemical and micro-biological analyses performed on potable water batches treated with the defined techniques show that the requirements are fully satisfied.

Evaluation of Bio-regenerative Life Support Systems in the frame of a Concurrent International Cooperation

With concurrent interests on Bio-regenerative Life Support Systems (BLSS), Italian and USA industrial and academic institutions, including Thales Alenia Spac e Italia (TAS-I), the University of Arizona (UA) an d the Sadler Machine Company have teamed in a collaboration effort. The collaboration has been providing personnel exchanges, sharing accumulated experiences and complementary competencies to establish synergies in the multi-dis ciplinary field of BLSS. The initial phase has linked aerosp ace engineering and system design competences together with other professional fields of plant sciences, controlled e nvironment production systems, mathematical modeling and computational analysis. The overriding theme of our activities is the succe ssful crop production, with effective resources uti lization, such that sufficient edible biomass will be continu ously provided to supply the desired percentage of the crew food calories from the system. The focus is mainly with crops targeted for space such as lettuce, sweet pot ato and tomato. Using available data and existing models, crop prod uction studies have been designed and implemented to achieve production results within a semi-closed structure t hat will be useful for correlation studies, as well as for strengthening the experiences with an operational p rototype BLSS. While the EDEN controlled plant growth chamber sited at TAS-I Recyclab has been operated to focus TAS-I engineers attention on the critical physical and biological aspects on a small scale demonstrator, the 22 m 3 Lunar Greenhouse (LGH) Prototype, sited at the Controlled Environment Agriculture Center (CEAC) at the University of Arizona (UA), has been upgraded and prepared for 9months of extensive utilization, supported by the N ASA Steckler Space Grant (Phase 1, January ‐ October 2010). Data will be evaluated within a TAS-I implemented model for the plant-life-support element, based on t he NASA Modified Energy Cascade (MEC) Model for Crop Growth 19,21 . Testing is in progress and data acquisition, management, utilization and improvements of the models will be completed. The subsequent system simul ations will be used for developing future designs of such facil ities. This paper describes the collaboration, focusing on the available facilities improvement, the definiti on of the data gathering, storage and elaboration strategies, the discussion of the preliminary results achieved and the illustration of the forthcoming activities.

New Concepts Evaluation of Flexible Water Bags for Space Applications

Onboard the International Space Station (ISS), water is well known to be an essential resource for life support: purification and recycling water systems are used to minimize its consumption. Nevertheless, it is necessary to provide periodically additional water through logistical support missions. With the dismissal of the Shuttle, procurement of equipment and supplies was delegated to the pressurized cargo modules, which transport rigid or flexible containers filled with potable water for crew consumer. This work shows the preliminary study results focused on the realization of flexible bags which can operate in commercial space missions for different operative scenarios. In one case the described bags would supply the two potable water qualities coexisting on the ISS with different bactericidal agents (iodine and silver for respectively American and Russian waters) and once drained they could be refilled or contain other fluids (e.g. waste water). The bags are foreseen to be collocated and transported inside modified Cargo Transportation Bags, starting from what already designed for the Cygnus commercial cargo, but adapted to the different needs. In addition, this paper briefly reports the related contribute to the study of the Reconfigurable Cargo Transportation Bags under development at NASA Ames.

Columbus Condensate Water characterization and wastewater revitalization

2. Moreover, in order to complete the investigation several batches of latent condensate have been produced in the RecycLAB laboratory. The wastewaters ersatz were obtained adding the needed chemical reagents in demineralized water according to the BVAD 2 recipe. In order to investigate the efficiency of the water treatment and revitalization via multi-filtration and membranes technology, a demonstrator has been designed, developed and acquired. The facility provides a pre-treatment unit (activated carbon, ion exchange resins, and filtration modules), an ultra-filtration ceramic module, two reverse osmosis modules, an UV-light disinfection and a post treatment module (active carbon, ion exchange resins). In order to minimize the consumables replacement, it has been verified that it is possible to regenerate latent condensate wastewater using only the reverse osmosis treatment stage. Chemical and physical properties of the regenerated water were found to be similar to demineralized water ones except for the TOC value.

UV-C Photocatalytic System for VOC's Removal

In the frame of space Advanced Life Support research, one of the targets of Thales Alenia Space RecycLAB laboratory is the study of photocatalysis for crew cabin as well as for space greenhouses air decontamination from volatile organic compounds (VOCs). For the purpose, the ZEUS demonstrator, a multi-functional system designed to characterize different air revitalization technologies and able to accommodate reactors of different shape, has been used. ZEUS was equipped with an ultraviolet (UV) lamp installed into a coaxial cylinder covered internally with a TiO 2 catalytic layer. The VOCs concentration was monitored by a gas chromatograph with flame ionization detector, connected to the demonstrator by an on-line sampling system. The first studied application was the degradation of ethylene, a phytohormone produced by plants that influences the growth and development processes, harmful to plants and their edible products in the case of a chronic exposure to high levels typical of closed environment greenhouses. This paper reports the data obtained using an UV-C lamp as a radiation source and multiple reactor configurations, in order to have the best performances for ethylene degradation. The possibility of the exploitation for the photocatalytic process of UV light directly available in space and on planets (e. g. Mars) is investigated as lower cost alternative to currently used consumable absorbent materials. For this purpose, a second experiment was performed using a lamp with UV-C irradiance equal to that reaching the Martian surface in optimum conditions.