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Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES. Past studies were reviewed in the light of today's technical advancement and a technology trade-off, supported by bread boarding, is performed. Current activities do concentrate on Critical technology selection and feasibility demonstration including bread boarding and testing, Methane Pyrolysis Assembly (MPA) operational interfaces with ARES Potential applications of MPA for other exploration capabilities, like in-situ resources utilization (Moon and Mars) The paper presents the achievements so far.

During the last years extensive work has been done to design and develop the Closed-Loop Air Revitalization System ARES. The potential of ARES e.g. as part of the ISS ECLSS is to significantly reduce the water upload demand and to increase the safety of the crew by reducing dependence on re-supply flights. The design is adapted to the interfaces of the new base lined Russian MLM module as possible location for a future installation of ARES. Due to the lack of orbital support equipment and interfaces to a waste water bus, to a feed water supply line and due to the availability of only one single vent line it was necessary to make the ARES process water loop as independent as possible from the host vehicle. Another optimization effort was to match the CO2 desorption profile with the available hydrogen flow to achieve a sufficient water recovery performance, while meeting all related safety requirements, minimizing complexity and improving reliability.

Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES, see figure 1. Past studies as presented in ref. /1/ had been reviewed in light of today's technical advancement and a technology trade-off, supported by bread boarding, resulting in the pre selection of the plasma technique to perform the Methane Pyrolysis. In parallel two methods for plasma provision are investigated: Direct Current Plasma, sustained by a discharge arc rotating in a nozzle to supply energy to the flowing through carrier gas. Micro Wave (MW) Plasma, sustained by a MW within a Quartz tube embedded in a MW resonator cuboid Study activities did concentrate on Development testing of pre selected plasma Pyrolysis technology.

European Space Agency's (ESA's) Columbus module was launched on February 7, 2008. This marks the completion of more than 10 years of development. It is a major step forward for Europe in the area of Environmental Control and Life Support (ECLS) as Columbus contains several major assemblies which have been developed in Europe. These include the Condensing Heat Exchanger, Condensate Water Separator and the Cabin Fans. The paper gives a short overview of the system and its features and it will report the experiences from the initial activation and operations phase.

ESA has been developing regenerative physicochemical air revitalisation technology for more than 20 years. The effort is now maturing into a flight demonstration experiment which is planned to be located in the Columbus module on ISS. The experiment shall be sized for a crew of three. It will comprise a CO2 concentration assembly, a Sabatier reactor and an electrolyser. The paper describes the adaptation of ARES to the available Columbus interfaces as well as ARES development status, performances, benefits to the ISS and operational agreements with ISS partners.

The launch and activation of ESA's Columbus module in early 2008 marked the completion of more than 10 years of development. Since then the Columbus ECLS is operating, including its major European ECLSS assemblies such as Condensing Heat Exchanger (CHX), Condensate Water Separator, Cabin Fans and Sensors. The paper will report the experiences from the first year of operations in terms of events, failures and lessons learned. Examples of this is the description of some off-nominal situations (such as Condensate Removal and IMV Return Fan failure, and relevant troubleshooting), and the preparation to Columbus Reduced Condensation Mode, as requested by NASA in order to minimize the crew time needed to empty Condensate Water Tanks in US Lab.

The Closed-Loop Air REvitalisation System ARES is a regenerative life support system for closed habitats. With regenerative processes the ARES covers the life support functions: 1. Removal of carbon dioxide from the spacecraft atmosphere via a regenerative adsorption/desorption process, 2. Supply of breathable oxygen via electrolysis of water, 3. Catalytic conversion of carbon dioxide with hydrogen to water and methane. ARES will be accommodated in a double ISPR Rack which will contain all main and support functions like power and data handling and process water management. It is foreseen to be installed onboard the International Space Station (ISS) in the Columbus Module in 2013. After an initial technology demonstration phase ARES shall continue to operate thus enhancing the capabilities of the ISS Life Support System as acknowledged by NASA [5]. Due to its regenerative processes ARES will allow a significant reduction of water upload to the ISS.

EADS SPACE Transportation GmbH designed, built and tested a condensate buffer to be located between a Condensing Heat Exchanger (CHX) and a Condensate Water Separator Assembly (CWSA), as part of the ECLSS of the European Columbus Module. Under zero-g conditions, the separation of water from an air-water mixture is always difficult, especially if a passive device is to be used such as the low power consuming Columbus CWSA. The additional buffer volume reduces condensate water peaks reaching the CWSA to a level that excludes an overloading of the CWSA and a release of free water droplets into the air return to the cabin. In the CHX/CWSA system this may only be necessary under worst case operational conditions and with a failure of the qualified hydrophilic coating of the CHX. The buffer design principle was confirmed via prior analyses and on-ground testing. The performance of such a condensate buffer under micro-g conditions was verified during parabolic flights.

A final test activity was carried out to complete the verification of the Environmental Control System (ECS) performances by experimentally reproducing the thermal hydraulic behaviour of the Environmental Control & Life Support Subsystem (ECLSS) section integrated in the overall Module, expected on analytical basis. A previous test campaign (called Columbus ECS PFM Test) carried out in EADS-Bremen in spring 2003 and described in paper number 2004-01-2425 showed some contradictory data concerning the air loop behaviour. These incoherent test results were related to the environmental and geometrical cabin loop conditions during the on-ground 1g test and to improper position of the sensor measuring the cabin temperature. For this reason a partial repetition of the test has been performed. In particular, this experimental campaign was focused on the verification of the cabin air temperature control, as a consequence of the Temperature Control Valve (TCV) movement.

The Columbus ECS PFM Test was intended as the final verification of the Module Thermal Design after a series of successful tests at subsystems level (e.g. the Active Thermal Control Subsystem and the Environmental Control and Life Support System) The test campaign has been articulated as a sequence of several test cases to investigate the main thermal aspects, to prove the Module thermal design in the extreme operative conditions and to correlate the thermal mathematical model (TMM). The interpretation of test results and the correlation confirmed that the thermal design of the module is adequate, but some areas of concern remain, mainly for the difficulty to translate to 0-g the results of a complex test in 1-g environment, and for some aspects of the air and cabin loops.

1 The Closed-Loop Air REvitalisation System ARES is a proof of technology Payload. The objective of ARES is to demonstrate with regenerative processes: the provision of the capability for carbon dioxide removal from the module atmosphere, the return supply of breathable oxygen within a closed-loop process, the conversion of the hydrogen, resulting from the oxygen generation via electrolysis, to water. The ARES Payload is foreseen to be installed - in 2012 - onboard the ISS in the Columbus Module. The operation of ARES - in a representative manned microgravity environment - will produce valuable operational data on a system which is based on technologies which are different from other air revitalization systems presently in use. The ARES Technology Demonstrator Payload development started in 2003 with a Phase B, see references [1], [2], [3] and [4]. ARES is presently in Phase C1 and a PDR is scheduled for the beginning of 2009.