Objective To address the bottlenecks in the application of wastewater biological treatment technology under space conditions,an experimental system for the biological treatment of space wastewater was constructed and its biochemical performance examined.The findings of this study will provide technical support for the biological treatment of space wastewater.Methods Based on the Membrane Aerated Biofilm Reactor(MABR)process,a biological treatment experimental system for space wastewater was constructed and conducted the continuous flow test for 77 days to investigate the performance of PVDF and PP membrane modules in the treatment of simulated air condensate.Results The results demonstrated that both membrane modules exhibited an average TOC removal rate of 90%,indicative of their effective organic matter removal capacity.In the air supply mode,the ammonia oxidation capacity was observed to be comparatively lower,whereas in the oxygen source without bubbling mode,the nitrogen oxidation rate and total nitrogen removal rate could be attained above 90%,indicating a notable degree of simultaneous nitrification and denitrification.The results demonstrated that the mode of gas supply had a significant impact on the nitrogen conversion performance.The abundance of nitrogen-converting bacteria in PP membrane module is higher than that in PVDF membrane module,indicating a better nitrogen-converting performance in PP membrane module.Conclusion The constructed wastewater biological treatment system is optimally suited for the treatment of air condensate,thereby offering a novel technical approach for space wastewater treatment.

Objective In this study,the gas exchange performance and impact patterns of microalgae culture based on hollow fiber membrane technology were investigated for the culture of space microalgae.Methods The effects of parameters and conditions such as gas flow rate,membrane area and liquid flow rate on the CO2 fixation efficiency and fixation rate of hollow fiber membrane modules were studied,and the gas exchange performance of different parameters were compared by fitting formula.Results The gas flow rate and membrane area have a significant effect on the gas exchange performance of the module.With the increase of gas flow rate,the fixation rate of CO2 increases at first and then stabilizes,and the fixation efficiency of CO2 shows a continuous downward trend;with the increase of membrane area,the fixation rate and fixation efficiency of CO2 increase significantly,while the liquid flow rate has no significant effect on the gas exchange performance of the module.The highest CO2 fixation rate was 168.24 mg/(L·h)when the membrane area was 0.3m2 and the gas flow rate was 2.0 L/min.Conclusion The use of hollow fiber membrane technology can solve the problem of two-phase flow management in the gas exchange between algae culture and atmosphere,which has a better effect on gas exchange,and can provide reference for the design of gas exchange module of space microalgae photobioreactor.

The control and utilization of microorganisms in space-based animal culture constitute a pivotal challenge underpinning research domains such as space life sciences and extraterrestrial life-support system.This paper systematically examines the origins,transmission routes,and latent risks of microbial contamination in space-based animal culture facilities.A comprehensive analysis is conducted on the advancements in on-orbit implementation of microbial containment strategies,including physical filtration systems,antimicrobial surface coatings,and environmental parameter optimization.Additionally,the study evaluates the prospective applications of probiotic consortia and functionally engineered microorganisms in enhancing animal welfare,stabilizing biosphere conditions,and enabling closed-loop waste recycling.Notably,this work highlights the paradigm shift from reactive microbial suppression to proactive microbiome engineering in space-based animal husbandry,thereby establishing a theoretical framework for sustainable development of space-based animal culture.