Parameter Optimization for Start-up of a Simultaneous Nitrification/Denitrification Membrane Aerated Bioreactor
Water is among the critical limited resources required to sustain human life in space. NASA has targeted 98% water recovery from wastewater in its efforts to transition from low earth orbit to long-duration exploration missions. A potential technology for this purpose is a membrane aerated bioreactor. This research investigated three independent parameters hypothesized to decrease the start-up time of a simultaneous nitrifying/denitrifying reactor, ultimately intended to oxidize organic carbon and convert ammonium to nitrogen gas. Using 12 small, ambient pressure membrane aerated bioreactors (MABR), we investigated the effects of three different parameters against a urine-fed control. The parameters included wastewater, addition of a quorum sensing molecule, and elevated temperature. The fastest start-up time was produced using the wastewater. These parameters decreased the startup time of the bioreactor until full-strength wastewater was reached, demonstrating a quicker and more reliable method to initiate biological wastewater processing for long duration spaceflight.