Space grade Biomethane production for Themis reusable stage demonstrator
Creators: name:  P. NOIR 
name:   M. KURELA 
Publisher: name: Proceedings of  the 9th European Conference for Aerospace Sciences. Lille, France, 27 June - 1 July, 2022
Year: 2022
Subjects: SUSTAINABLE SPACE
LOGISTICS

description: During the last decade numerous projects of methane/oxygen space engines have been undertaken in the world. The tradeoffs that were performed indicated the advantages of those propellants with regards to the existing state of art of LOX/LH2 or LOX/kerosene engines, such as simpler propulsion systems leading to production and exploitation cost reduction, better reliability and improved safety. One of the elements of that tradeoff concerns the industrial and technological maturity of propellants production means which impact cost performance and environmental issues. The comparison of the propellant production chains, associated to the specific situation of French Guiana and its space industry [2], allowed to define the specifications and a preliminary concept of biomethane production for future launchers using oxygen and methane that is presented in the article. It proposes to implement the compact installation that is able to provide the methane propellant for a prospective, reusable launcher, passing through the first step in form of Themis demonstrator reusable stage [1]. It aims to perform this production with a stringent availability of propellant that is compatible with important launch rate up to 10 launches per year and to provide the propellant with the quality level that is compatible with the space propulsion system ( Grade A MIL-PRF-32207 ). The proposed concept takes into account the full life cycle of the propellants, starting from the definition of raw materials available locally in French Guiana, passing through the economy of their acquisition, logistics of transport, storage and then conversion in anaerobic generators into biogas which is purified in the last step to the final product methane. The retained concept for biogas production relies on methanization due low energy consumption thanks to natural organic material decomposition. The requirements allow small quantity of impurities, compatible with use in the reusable space engine Prometheus. In the end the propellant is supposed to be stocked in the form of cryogenic liquid and used, when required, for Themis demonstrator launches. The strategies to optimize each step of that production, to limit the propellant loss, process costs and emissions impacting environment are presented as well as the elements of scaling up of that demonstration installation to the target launcher industrialization needs. The article follows on with the comparison with other methane production source and the state of art [3] for space propellants production means and their logistic chains to evaluate the expected gains in terms of costs and environmental impacts, typically methanol reforming for hydrogen production and water electrolysis for green hydrogen production. The article also put in evidence the social and economic interest of this propellant production source by contributing to initiate a circular economy involving agriculture and organic waste valorization in French Guiana in line with European renewable rules. In conclusion the preliminary results confirm the interest of producing biomethane in French Guiana for the reasons of cost savings and positive environmental impacts. The follow up with detailed concept design and development of the dedicated unit is being organized. References [1] J. Vila, J. Hassin, Technology acceleration process for the THEMIS low cost and reusable prototype, 8TH European Conference for Aeronautics and Space Sciences (EUCASS), 2019 [2] M.Kurela, P.Noir, Methane production chain assessment for space launchers, 22e Congres de Maitrises des Risques et Surete de Fonctionnement ?22, 2020 [3] Caposciutti, G.; Baccioli, A.; Ferrari, L.; Desideri, U. Biogas from Anaerobic Digestion: Power Generation or Biomethane Production? Energies 2020, 13, 743