空间微藻光生物反应器地面试验样机研制

Development of a Ground-based Micro-algae Photo-bioreactor Experimental Facility for Using in Space

目的针对空间环境条件特点,研制空间微藻光生物反应器地面试验样机,为未来长期空间飞行、深空探测等飞行任务的乘员提供藻蛋白和O2,并清除密闭环境中的CO2等废气。方法根据未来空间条件下使用要求,进行系统设计、加工,研制成空间微藻光生物反应器,然后进行微藻培养验证实验。结果该装置共包括生物反应器主体、光源、CO2供应组件、溶氧脱除组件等9个部分。在该装置中,采用了一种新型的光生物反应器主体为微藻的生长提供场所;研制成供气膜功能组件,为微藻提供生长所需的CO2气体,提高了CO2的吸收利用率;采用膜技术,研制成脱气膜功能组件,及时脱除了藻液中的溶解氧,不仅为乘员提供了呼吸用氧,提高了藻体的生长速率,而且大大地降低了空间微重力条件下的气/液分离负荷。验证试验结果表明:该装置系统运行良好,其能耗、体积、藻蛋白生产能力等均满足设计要求。经7d培养后,培养液的藻体密度从0.174g(DW)/L增加到4.064g(DW)/L,平均每天的藻蛋白生产能力高达11.1g(DW)。结论研制的微藻光生物反应器试验样机运行稳定,藻体生长良好,O2的脱除和CO2的供应原理适合空间微重力环境下使用要求。

Objective To develop a ground-based micro-algae photo-bioreactor experimental facility for using in space. Methods Project planning, design drafting, manufacture and debugs were conducted basing on demand of using in space. Finally, a demonstration test for producing algae was done. Results The facility comprises nine subsystems, including a reactor, a light unit, a CO2 supplying unit and an O2 removing unit. A new type of reactor was adopted, where the micro-algae grew. A membrane module was introduced to develop a CO2 supplying unit. By this way, capacity of algae absorbing and utilizing CO2 was improved. An O2 removing unit was manufactured by applying the membrane technique, it not only removed the dissolved oxygen immediately and gave it to the human, but also alleviated the load of separating gas from liquid in weightlessness condition. The experimental test results demonstrated that the density of algae in the photo-bioreactor in- creased from 0. 174 g （ DW）/L to 4. 064 g （ DW）/L after 7 d growing. Its productivity for the microalgae was up to 11. 1 g （DW）/d. Conclusion The facility has reasonable technical indexes, and smooth and reliable performances. The micro-algae can grow normally in the bioreactor. The principle of the bioreactor of providing CO2 for algae and taking O2 from the culture medium is suitable for the demand under space conditions.