Development of a combined anaerobic and aerobic membrane bioreactor for wastewater treatment and reclamation in terrestrial-based controlled ecological life support system

Abstract

A novel wastewater treatment and reuse system (WTRS) combining an anaerobic membrane bioreactor (AnMBR) and an aerobic membrane bioreactor (MBR) with the design capacity of 115 L/d was developed for a terrestrial-based controlled ecological life support system (CELSS). Results clearly showed that the WTRS realized mineralization of organic compounds and reservation of nitrogenous nutrient, therefore converting the effluent into replenishment for the hydroponic system. Trace gas emission from the WTRS could meet requirements for the whole CELSS. Compared with physico-chemical processes, the specific consumables consumption of the WTRS was advantageous but its specific energy consumption is still in need of improvement. Results of microbial community analysis were consistent with the running state of the AnMBR and the MBR.

Development of Nitrogen Recycling Strategies for Bioregenerative Life Support Systems in Space

“…More recently, China completed a 106-day terrestrial manned mission in the Lunar Palace 1 facility. A BLSS was successfully used to support a crew of four with minimal external input of food, water, and oxygen for the duration of the trial ( Xie et al, 2017 ; Cheng et al, 2019 ). During the experiment, nitrogen was recovered from urine with an efficiency of 20.5% through reduced-pressure distillation, where ammonia was distilled together with the water vapor.…”

“…In the second phase of Lunar Palace, an anaerobic and aerobic membrane bioreactor will replace the current setup. In preliminary experiments preceding a new manned mission in Lunar Palace, successful ureolysis has been observed in the anaerobic reactor, while the ammonium removal efficiency in the aerobic reactor sits between 80 and 99% during stable operation ( Cheng et al, 2019 ).…”

“…While the former technologies are promising for improving the overall process of urine nitrification, the use of an anaerobic bioreactor followed by an aerobic bioreactor as will be applied in the Lunar Palace also show promise ( Cheng et al, 2019 ). Thus, in recent years, exciting concepts have been demonstrated for the combination of physicochemical and biological elements for urine processing in space.…”

Water reclamation and reuse

“…In addition, the treated effluent supported 100% germination of Raphanus sativus seeds and enhanced all growth parameters of radish plants. Cheng et al (2019) evaluated a combined anaerobic/aerobic membrane bioreactor with a design capacity of 115 L/day used in a terrestrial‐based controlled ecological life support system for wastewater treatment and reuse. The effluent, with COD, , and below 30, 20, and 2 mg/L, respectively, was determined to be suitable for use in a hydroponic system.…”