Demonstration of a Full Scale Integrated Membrane Aerated Bioreactor- Ionomer-Membrane Water Purification System for Recycling Early Planetary Base Wastewater.
Long term space habitation outside of low Earth orbit requires near complete recycling of wastewater. Current systems rely on chemical pretreatments and are not capable of treating the diversity of wastewaters expected to be produced from an early planetary base (EPB). Hybrid life support systems that combine biological treatment with advanced desalination systems can provide robust treatment systems with lower consumable mass and the capability to treat all proposed wastewaters as well as produce near potable quality. A habitation wastewater processing architecture was developed that combines three technologies: a Membrane Aerated Bioreactor (MABR), an Ionomer-membrane Water Purification (IWP) system, and a Gas-phase Trace Contaminant Removal (GTCR). The integrated system was continuously tested for 5 months. Testing included a baseline DI water run, three test periods utilizing an EPB wastewater, and a final DI water test period to characterize the extended testing impacts on the longevity of the system. The MABR acted as a variable volume universal wastewater collection tank and discharging wastewater to the IWP once per day. The distillation vessel continuously stored solids throughout each run (up to 54 days). Results of the first 5 test periods demonstrate an average water production rate of 14.6 L/day at a 46% desalination duty cycle. The quality of the water produced by the system was consistent with TDS, NOx, NH4, Cl-, and SO4 all within ISS potable limits. DOC satisfied terrestrial potable requirements but exceeded ISS limits while pH fell slightly below. The system had a water recovery rate of 95.1% including the initial mass wetting. Nominal test periods 2 and 3 surpassed that with recovery rates of 96.9% and 96.4%, respectively. Clean water production rates for the last test period after approximately 100 days of effluent processing equaled initial testing performance highlighting the robust performance of the design.
Barry Finger Paragon, Space Devlopment Corporation
Christian Harkins, Texas Tech University
ICES303: Physio-Chemical Life Support- Water Recovery & Management Systems- Technology and Process Development
The 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.