Closing the Water Loop for Exploration: 2018 Status of the Brine Processor Assembly

The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project and Paragon Space Development Corporation are developing a four-person Brine Processor Assembly (BPA) for demonstration on the International Space Station (ISS). BPA will recover water from urine brine produced by the ISS Urine Processor Assembly (UPA) and it is expected to achieve water recovery rates significantly greater than the 75-90% that is currently recovered by the UPA’s Vapor Compression Distillation (VCD) subsystem. By increasing overall water recovery on ISS to greater than 98% BPA will demonstrate a critical capability needed to close the brine processing technology gap identified in NASA’s Water Recovery Technology Roadmap. BPA utilizes the forced convection of spacecraft cabin air coupled with a robust membrane distillation process to recover purified water from 22.5 liters of brine within a 26 day cycle. An ionomer-microporous membrane pair contains the brine while transferring purified water vapor to the cabin air. The water vapor is collected by the existing spacecraft condensing heat exchangers, which already recover metabolically produced water vapor as humidity condensate. This paper will discuss progress to-date on meeting critical technical and ISS integration milestones, and provide an overview of the remaining work required to successfully deliver the proto-flight unit to ISS in 2019.