Oxygen Regeneration by Algae Cultivation in Photo-Bioreactor for ISS Cabin Technology Demonstrator

Oxygen regeneration from ambient carbon dioxide is a fundamental technology building block for future life support systems for space applications. BIORAT1 Phase B2 project consists in the development of the Preliminary Design Review (PDR) level design of an On Board Demonstrator (OBD) to be hosted in European Drawer Rack 2(EDR2) facility on board of the ISS. The core of the OBD is a Photo-Bioreactor (PBR) filled with spirulina (Limnospira indica PCC 8005) producing oxygen from carbon dioxide and light by photosynthesis. A Liquid Loop (LL) transports the oxygen & carbon dioxide dissolved into the cultivation medium liquid between the Photobioreactor (PBR) and the ISS cabin ambient air. The Gas Exchange Module (GEM) enables the exchange of Oxygen & Carbon Dioxyde separates the cultivation medium liquid to the ambient air while keeping the liquid inside the LL. The design of this flight hardware is supported by tests results obtained with a Bread Board Model (BBM). In this paper, we present the results of the long duration spirulina cultivation test performed with the BBM. allowing verification of the long term functionality of the PBR & LL including the GEM. The PBR performances together with correlation to the model of the cultivated algae growth and oxygen production are presented. Future development and expected results and perspectives are also presented and discussed.