空间站环境控制与生命保障系统微生物腐蚀行为与控制方法

 空间站环境控制与生命保障(环控生保)系统微重力条件下,空间站密闭狭小舱内的真菌和细菌等微生物主要来自航天员生理代谢产生的废物(尿液、粪便),日常生活和工作中形成的废弃物,以及在密闭生态系统中进行食物、气和水反复净化和再生处理所应用的微生物。空间站环控生保系统中的水、冷凝水、废水等介质中极易滋生微生物,并通过微生物产生具有腐蚀性的代谢产物,如硫酸、有机酸、硫化物和氨等,恶化金属材料腐蚀的环境。本文综述了微重力条件下的微生物生物效应、空间站材料微生物腐蚀行为、材料微生物腐蚀防护技术等3个方面,讨论了太空特殊的微重力环境下微生物生理生化性状的变化及其与材料间的复杂相互作用,认为开展微重力条件下相关材料的微生物腐蚀实验研究,明确生物膜的形成及其腐蚀作用机制,开发新型抗微生物防护材料体系,对保障空间站环控生保系统材料安全服役具有重要意义。

Corrosion Behavior and Control Methods of Microbiologically Influenced Corrosion of Space Station Environmental Control and Life Support System

Microbes including fungus and bacteria in confined and limited capsules of space station environmental control and life support system under microgravity mainly come from astronaut metabolic wastes(stool and urine) and domestic garbage. In addition, repeated purification and recycle of food, gas and water in closed ecological facility need certain microbes, which add to the amount and species of microbes in capsules. Meanwhile, the medium such as condensate and water waste creates good breeding ground for microbes, of which corrosive metabolite such as sulfuric acid, organic acid, sulfide and ammonia and so on, will deteriorate the corrosion environment. The biological effect of microbes under microgravity condition, the microbial corrosion behavior to space station material and microbial corrosion protection technology are reviewed. Meanwhile the effect of special space microgravity environment to the physiological and biochemical characters of microbes as well as the complex interaction process between materials and microbes are discussed. It is suggested that performing microbial corrosion experiment research on related materials, expliciting the formation process of biofilms as well as corresponding corrosion mechanism, and developing new antimicrobial protection material system, are important to guarantee the safety of space station environmental control and life support system. Finally, some suggestions are provided for the relevant research and the developments, which are expected in the future.