Validation of Lunar Water Extraction and Purification Technologies for In-Situ Propellant and Consumables Production

Project Information

LUWEX

Grant agreement ID: 101081937

DOI

10.3030/101081937

Project closed

EC signature date 19 October 2022

Start date 1 November 2022

End date 31 December 2024

Funded under

• Digital, Industry and Space

Total cost

€ 1 499 008,25

EU contribution

€ 1 498 220,25

Coordinated by

DEUTSCHES ZENTRUM FUR LUFT - UND RAUMFAHRT EV
Germany

Periodic Reporting for period 1 - LUWEX (Validation of Lunar Water Extraction and Purification Technologies for In-Situ Propellant and Consumables Production)

Reporting period: 2022-11-01 to 2024-12-31

Summary of the context and overall objectives of the project

Sustainable space exploration requires the development of In-Situ Resource Utilization (ISRU) technologies, which encompass all processes that utilize local resources to generate useful products for robotic and human exploration. Among the available resources, water is the most versatile and most needed in space exploration. Water can be directly used as consumable for astronauts or electrolyzed to hydrogen and oxygen, a very effective rocket propellant combination. However, in-situ water extraction is challenging and the required technologies are not yet fully developed. The project team developed and validated a complete in-situ water process chain including water extraction, purification and quality monitoring. An integrated test setup was built to validate the operational capabilities of these technologies and also of the whole process chain under realistic environmental conditions using a lunar dust-ice simulant. The interdisciplinary nature of LUWEX combines research and innovation in space engineering, space science and exploration, geophysics and terrestrial water systems distributed among large space industry (Thales Alenia Space Italia), research organizations (DLR), SMEs (Liquifer Systems Group, Scanway) and academia (Technische Universität Braunschweig, Wroclaw University of Science and Technology) from four European countries (Germany, Italy, Austria, Poland).

Project goal:
The development, integration and validation of lunar water extraction and purification technologies for in-situ propellant and consumables production for future space exploration missions.

Project objectives:
• Development of water extraction, purification and quality monitoring technologies for an in-situ raw water process chain.
• Designing and manufacturing an integrated validation test setup to provide a proper test environment as an essential preparatory activity for future space exploration.
• Validation of in-situ raw water technologies in an integrated test setup in a laboratory environment.
• Advancing the European excellence in space exploration by developing and validating leading edge in-situ resource utilization technologies.
• Improving the interdisciplinary collaboration and leveraging synergies of industry, academia and institutional research within Europe.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

As part of the LUWEX research project (Validation of Lunar Water Extraction and Purification Technologies for In-Situ Propellant and Consumables Production), researchers have developed a process with which they can extract and purify water from icy moon dust (regolith) in order to supply rocket fuel and drinking water for astronauts stationed on the lunar surface in the future. This process has now been successfully trialled in experiments.
In the thermal vacuum chamber of the CoPhyLab (Comet Physics Laboratory) at TU Braunschweig, the project team mixed self-produced ice and synthetic lunar regolith to create a dust-ice simulant, from which the water can then be extracted in the thermal vacuum chamber. For the ice, a mist of very fine water droplets is shock-frozen in liquid nitrogen. This produces individual round water ice particles with a radius of 2.4 micrometres, which corresponds to around one twentieth of a human hair. These are then mixed with the lunar regolith.
The lunar ice simulant is then placed in the water extraction system developed by DLR. This system is located inside the thermal vacuum chamber, which offers moon-like conditions. The remaining atmosphere is then pumped out and the simulant is heated and stirred to distribute the heat evenly. Due to the low pressure, the ice does not liquefy but converts directly into water vapour. This gas then collects on copper pipes that are cooled to -150 degrees Celsius with liquid nitrogen. There, the gas condenses back into ice. This is how the ice and lunar regolith are separated. When enough ice has collected on the copper pipes, they are heated and the ice slides downwards, where it liquefies into water. The DLR in Bremen has developed this subsystem for extracting the water. At the end of the experiment, the water is treated and its quality checked.
The scientists tested various samples with different proportions of lunar regolith and ice in order to identify the optimum process parameters for water extraction. The aim of the project was to extract a maximum amount of water on the moon with minimum energy. One question was which temperature and stirring speed are best suited for this. In the second step, Thales Alenia Space treated and purified the extracted water. Sensors measured the water quality and samples were analysed and prepared in the laboratory.
The interdisciplinary LUWEX team from Germany, Austria, Poland and Italy has set itself the goal of developing a new type of water extractor. Each project participant is providing one or more subsystems or infrastructures. The institutions and companies involved in the project alongside DLR are the Technical University of Braunschweig, LIQUIFER Systems Group, Thales Alenia Space, Wroclaw University for Science and Technology and SCANWAY SPACE. The process chain was successfully tested under relevant (moon-like) conditions and therefore achieved TRL 4.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The project team successfully developed key technologies for an in-situ raw water process chain. The key technologies encompass a water extraction device and a water vapour capturing and liquefaction device (both developed by DLR), a water purification and storage device (developed by Thales Alenia Space) and a water quality and condition monitoring device (developed by Scanway and WUST). All subsystems have been designed in a way, that enables them to be interconnected to form a complete water processing chain.
This in-situ raw water process chain is the first of its kind that includes all necessary steps to extract water on the lunar surface and purify it for further use in water electrolysis for propellant production and for astronaut consumption. The process chain was successfully tested under relevant (moon-like) conditions and therefore achieved TRL 4.
With this result, the different subsystem and the whole process chain can be further developed. Investigation on the next steps towards a future moon surface mission and towards terrestrial applications have been performed. Based on this activity, the water extraction and capturing subsystem is best suited for a near-term technology demonstration on the lunar surface and the water purification subsystem has good potential for a future terrestrial application in remote locations.
In order to prepare for a future space application, the next step is to reach TRL 5/6. To achieve this further development of the components is required. Especially, space-proven light-weight material needs to be selected for the water extraction and capturing subsystem, which until now was built using customized stainless-steel vacuum chamber components.
Besides the technological impact, the project team established contacts with different space companies which are currently planning to or which are already developing lunar landing and mobility systems. These contacts will become useful once the technology maturation is high enough to go into the planning stage of a concrete space mission.

LUWEX experimental setup without annotations

Extracted water after purification

Water purification and quality control subsystem

LUWEX experimental setup with annotations for each subsystem

Extracted water before purification

Project logo

Icy-lunar-regolith simulant