Technical Paper
CO2/O2 Recycling Through Micro Algae Culture for Life Support System in a Reduced Gravity Environment, Such as in Space
1999-07-12
1999-01-1960
We have reported that Euglena, a photosynthetic alga, has the ability to grow in a high CO2 atmosphere and yield great biomass due to the induction of chlorophyll biosynthesis under high CO2 conditions. In the present study, we investigated some microalgal culturing systems for CO2 elimination and O2 regeneration in closed air on the ground by using the photosynthetic alga, Euglena gracilis. z. In the first part of our experiments, we focused on the effects of CO2 and light intensity in the present culture system. We investigated to determine the optimum culture conditions for a microalgal culture system that functions effectively in the controlled ecological life support systems (CELSS). We determined the maximum elimination rate under a high concentration of CO2 with stirring of the supply gas by bubbling. We found that the maximum CO2 elimination rate or gas exchange performance under a 10 % concentration of CO2 was about 2.3 times higher than its low concentration of CO2 (0.04 %).
