Membrane-Based Bioprocessor for Life Support Wastewater Reclamation

Although bioprocessors have been successfully tested in ground test experiments as primary wastewater processors [1, 2 and 3], the transition required for operation of a bioprocessor in microgravity is complicated by the absence of gravity and buoyancy-driven convection. Gases are present in the wastewater bioprocessor from numerous sources including aeration, metabolic production and operation. This paper presents an innovative approach to the delivery of metabolically-required oxygen to a bioprocessor. A bioprocessor that provides oxygen delivery and bacterial support using membranes has been developed and tested during the past two years. Bench-top laboratory results have demonstrated that Total Organic Carbon (TOC) degradation above 95%, and nitrification above 80% can be maintained, while denitrification typically ranged between 5-25% in a membrane bioprocessor system (MBS). Based on the bench-top MBS testing, a scaled membrane biological wastewater processor (MBWP) was designed, fabricated, and delivered to NASA Johnson Space Center (JSC). Currently, a comprehensive solution for a microgravity-compatible bioprocessor is being pursued which can meet performance requirements and address all phase management issues.